bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring Bark‐Water Interaction Effects on Stemflow Nutrient Concentrations in Urban Trees
Authors: Lima Marcelle Teodoro , Mathias Samir Leite , Guandique Manuel Enrique Gamero , de Menezes Aparecido Junior , Van Stan John Toland , Tonello Kelly Cristina
Published: October 2024

This study investigates the influence of bark properties on nutrient fluxes in urban environments, focusing on the relationship between bark wettability, chemical composition, and the concentrations of nutrients in stemflow and adjacent soil across eight urban tree species. Through a comprehensive analysis involving chemical assays and ecohydrological measurements, we explored how variations in bark characteristics affect water interaction and subsequent chemical dynamics within urban landscapes. Contrary to the initial hypothesis that bark properties would significantly influence nutrient flux, results revealed a complex scenario where environmental and anthropogenic factors in urban settings seemingly overshadow the direct impact of bark characteristics on nutrient dynamics. Our findings indicate that while bark properties such as wettability and chemical composition do vary among tree species, these variations do not directly correlate with significant differences in stemflow or soil nutrient concentrations. This suggests a homogenising effect of urban environments on ecohydrological processes, highlighting the need for a broader understanding of urban forest ecology that incorporates both biological traits and urban‐specific environmental influences. This research contributes to the field of urban ecohydrology by underscoring the complexity of nutrient fluxes in urban forests and suggesting that effective urban tree management requires an integrated approach that considers the interplay between tree physiological traits and urban environmental conditions. Our study calls for further research to unravel the intricate dynamics of urban ecosystems, aiming to enhance the sustainability and ecological benefits of urban forests.
Regionalization Strategy Guided Long Short‐Term Memory Model for Improving Flood Forecasting
Authors: Ye Kejia , Liang Zhongmin , Chen Hongyu , Qian Mingkai , Hu Yiming , Bi Chenglin , Wang Jun , Li Binquan
Published: October 2024

Flood forecasting in data‐scarce catchments is challenging for hydrologists. To address this issue, a regional long short‐term memory model (R‐LSTM) is proposed. Given the diverse physical characteristics of sub‐catchments, this model scalarises the runoff data based on catchment attributes including area, confluence path length, slope and minimum and maximum runoff values, thereby eliminating the local influence and producing a geomorphological‐runoff factor as the model input. To assess the effectiveness of R‐LSTMs for flood forecasting in data‐scarce basins, the Jiaodong Peninsula in China was selected as the study area. The proposed R‐LSTMs are compared with local LSTMs, regional LSTMs that do not use catchment attributes, or regional LSTMs that incorporate catchment attributes in different ways. The results show that R‐LSTMs outperform the benchmarking LSTM models, especially in the simulation of flood peaks. The study indicates the potential of regionalization and the benefit of building the scalarised inputs of runoff data for regional LSTM that consider catchment attributes meticulously. The research findings can provide a reference for flood forecasting in data‐scarce regions.
Quantifying the Role of Calibration Strategies on Surface‐Subsurface Hydrologic Model Performance
Authors: Abbas Salam A. , Bailey Ryan T. , White Jeremy T. , Arnold Jeffrey G. , White Michael J.
Published: October 2024

Distributed, coupled surface‐groundwater hydrologic models are high‐dimensional, given the necessity to reflect the spatially diverse nature of complex hydrologic processes. Furthermore, inverse/inference problems involving these high‐dimensional models are naturally ill‐posed, given the limited information content of state observations that are typically assimilated. Many inversion/inference algorithms do not cope well with high dimensionality, leaving the practitioner to make subjective choices related to uncertain model inputs. The objective of this study is to evaluate the impact of these subjective calibration choices within a formal sensitivity analysis, uncertainty analysis, and parameters estimation (SA‐UA‐PE) framework on model testing for a surface‐subsurface hydrologic model. In doing so, we address the concepts of ‘over‐parameterisation’ and ‘under‐parameterisation’. We completed a series of numerical experiments, testing several otherwise subjective aspects of the calibration process: (1) the number (5, 10, 15, 20) and type (soil, aquifer, land surface, channel) of calibration parameters selected); (2) the type of state observations assimilated (streamflow, groundwater head); and (3) the length of testing period (1 to 14 years), using monthly streamflow and groundwater head as testing data. The experiments were completed for models of the Winnebago River watershed (Minnesota, Iowa), (significant tile drainage) and the Nanticoke River watershed (Delaware, Maryland (significant groundwater‐channel interactions). The selected hydrologic model is SWAT+, using the gwflow module for physically based groundwater storage and flow modelling, and simulations are run for the 2000–2015 period. Through this process, we found that increasing the number of parameters from 5 to 15 improves the representation of streamflow, principally through an improvement of groundwater storage representation and baseflow generation, but minimal improvement when increasing to 20 parameters. Therefore, the SA‐UA‐PE process can be optimised based on an ideal number of parameters that yield adequate results while maintaining a lower computational burden. The method presented here can be used for any watershed, using integrated surface‐subsurface hydrologic models.
Advancing the utilization of 2D materials for electrocatalytic seawater splitting
Authors: Ligani Fereja Shemsu , Mehmood Andleeb , Ji Qianqian , Raza Waseem , Hussen Ahmed , Hu Jie , Zhai Shuo , Cai Xingke
Published: October 2024

Applying catalysts for electrochemical energy conversion holds great promise for developing clean and sustainable energy sources. One of the main advantages of electrocatalysis is its ability to reduce conversion energy loss significantly. However, the wide application of electrocatalysts in these conversion processes has been hindered by poor catalytic performance and limited resources of catalyst materials. To overcome these challenges, researchers have turned to two‐dimensional (2D) materials, which possess large specific surface areas and can easily be engineered to have desirable electronic structures, making them promising candidates for high‐performance electrocatalysis in various reactions. This comprehensive review focuses on engineering novel 2D material‐based electrocatalysts and their application to seawater splitting. The review briefly introduces the mechanism of seawater splitting and the primary challenges of 2D materials. Then, we highlight the unique advantages and regulating strategies for seawater electrolysis based on recent advancements. We also review various 2D catalyst families for direct seawater splitting and delve into the physicochemical properties of these catalysts to provide valuable insights. Finally, we outline the vital future challenges and discuss the perspectives on seawater electrolysis. This review provides valuable insights for the rational design and development of cutting‐edge 2D material electrocatalysts for seawater‐electrolysis applications.

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Sparse‐View Photoacoustic Reconstruction Method for Diabetic Retinopathy Using Feature Fusion Network
Authors: Chang Xiaohan , Cai Lingbo , Wang Jianlei , Dong Hongyang , Han Jing , Wang Chun
Published: October 2024

Diabetic retinopathy is one of the most prevalent microvascular complications of diabetes mellitus, and photoacoustic imaging is an effective method for imaging diabetic retinal vessels. Photoacoustic imaging is an emerging noninvasive imaging method based on the photoacoustic effect, which offers advantages of contrast, resolution, and depth imaging. Appropriate photoacoustic reconstruction methods are essential for obtaining high‐quality photoacoustic images. In this study, a multi‐input self‐attention multiscale feature fusion network (SAMF‐Net) is proposed for photoacoustic reconstruction. The algorithm accepts two inputs, namely the original photoacoustic signal and the traditional reconstructed image. Furthermore, a global feature extraction module based on the self‐attention mechanism is employed to focus on the global information. The results demonstrate that the proposed method exhibits superior reconstruction capability under different sparse detection views. The method has instructive value for photoacoustic image reconstruction and has the potential for further application in the diagnosis of diabetic retinopathy.
Engineering Shape to Overcome Contraction: The Role of Polymer–Collagen Hybrids in Advanced Dermal Substitutes
Authors: Leon‐Valdivieso Christopher Y. , Bethry Audrey , Pinese Coline , Dai Michèle , Pompee Christian , Pernot Jean‐Marc , Garric Xavier
Published: October 2024

Collagen gels are the standard dermal equivalents par excellence, however the problem of rapid cell‐mediated contraction remains unresolved. Therefore, the development of hybrid constructs (HCs) based on collagen and polymeric scaffolds is proposed to address the mechanical instability that usually limits the formation of new, functional tissue. Equally important, these synthetic structures should be temporary (degradable) while ensuring that cells are well‐adapted to the new extracellular environment. In this study, we screened a library of scaffolds made of various polymers, including homopolymers of polycaprolactone (PCL) and poly D,L‐lactide (PLA50), their blends (PCL/PLA50), and copolymers (poly(D,L‐lactide‐co‐caprolactone), PCLLA50) to prepare HCs in a layer‐by‐layer fashion. The properties of polymers and copolymers along with their processability by electrospinning and 3D‐printing were evaluated. Then, we assessed the HCs resistance toward cell‐mediated contraction as well as the degradation of the polymeric scaffolds. Our results indicate that scaffolds with higher PLA50 content (e.g., PLA50 100%, PCL/PLA50 or PCLLA50, both at 50/50 caprolactone‐to‐D,L‐lactide molar ratio) presented more drawbacks in terms of handleability and processing, while those with greater PCL presence showed structural steadiness and ease to use. All the scaffolds integrated well with the collagen gel to form the corresponding HCs. With few exceptions, the HCs demonstrated good resistance to cell‐derived contraction over 3 weeks. Notably, HCs based on PCLLA50 90/10 (both versions, electrospun or 3D‐printed) performed best, showing only a 5%–17% area reduction compared to the 93% observed in collagen‐only gels. This copolymer displayed hydrolytic degradation depending on its shape, with up to 45% and 65% loss of molecular weight for the electrospun and 3D‐printed forms, respectively, correlating with their progressive change in mechanical features. HCs containing PCLLA50 90/10 also exhibited a better fibroblast distribution, enhanced myofibroblastic differentiation, and a three‐fold increase in cell proliferation (when the electrospun type was used) compared to collagen controls. These findings were instrumental in selecting a potential HC that might be used for future experiments in vivo.
A review article on the development of dopaminergic neurons and establishment of dopaminergic neuron–based in vitro models by using immortal cell lines or stem cells to study and treat Parkinson's disease
Authors: Göksu Azize Yasemin
Published: October 2024

The primary pathological hallmark of Parkinson's disease (PD) is the degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta, a critical midbrain region. In vitro models based on DA neurons provide a powerful platform for investigating the cellular and molecular mechanisms of PD and testing novel therapeutic strategies. A deep understanding of DA neuron development, including the signalling pathways and transcription factors involved, is essential for advancing PD research. This article first explores the differentiation and maturation processes of DA neurons in the midbrain, detailing the relevant signalling pathways. It then compares various in vitro models, including primary cells, immortalized cell lines, and stem cell‐based models, focusing on the advantages and limitations of each. Special attention is given to the role of immortalized and stem cell models in PD research. This review aims to guide researchers in selecting the most appropriate model for their specific research goals. Ethical considerations and clinical implications of using stem cells in PD research are also discussed.
Design of Coplanar Stripline Bandpass Filter With Reconfigurable Filter Switch
Authors: Kho Edison , Basu Banani , Nandi Arnab
Published: October 2024

This article has designed a bandpass filter using a coplanar stripline stub (CPS) resonator consisting of open and short‐ended strip lines connected to the PIN diode switches. The use of spurline stub resonators inside CPS results in bandpass and bandstop filters, depending on the PIN diode switch configurations. The work presents a novel circuit architecture aimed at reducing the parasitic resonance of the spurline resonators and acquiring the necessary series stub characteristics. The proposed filter resonates at 6.9–9, 1.7–4.7, and 8.4 GHz when the PIN diodes are forward and reverse‐biased, respectively. It also resonates at 1–2.1, 4.8–5.3, and 6.9–9 GHz when one diode is reverse‐biased, and the other is connected in forward bias. An insertion loss below −0.55 dB and a return loss less than 10 dB have been obtained during simulation and measurement. The designed filter can find different applications for the 1.8 GHz GSM band, 2.4/5.8 GHz (WLAN), 3.6 GHz (WiMAX), long‐term evolution (LTE), and WIFI. The filter can be used in various multi‐frequency systems owing to its compact size. The measured and simulated findings of the proposed CPS spurline stub resonator wideband bandpass filters are substantially consistent.
Combined Impacts of Autumn Snow Cover on the Tibetan Plateau and Northeast Asia on the Winter Eurasian Temperature
Authors: Chen XinHai , Jia XiaoJing , Xie QianJia , Wu Renguang
Published: October 2024

This study explores the combined effects of autumn snow cover anomalies on the Tibetan Plateau (TP) and Northeast Asia (NEA) on winter Eurasian temperature using observational data for the period 1972–2021 and a linear baroclinic model (LBM). Distinctive wintertime temperature patterns are found across the Eurasian continent corresponding to increased autumn snow cover in NEA when TP experiences normal, above‐normal, or below‐normal snow cover condition. In the scenario with an anomalous increase in autumn snow cover in NEA in combination with normal snow cover condition in TP, the overall winter temperature anomalies tend to be generally weak across the Eurasian continent. In years when autumn TP snow cover is above normal, the spatial distribution of winter temperature anomalies over the Eurasian continent associated with more NEA snow cover exhibits a ‘cold Arctic‐warm Eurasia’ (CAWE) pattern. The emergence of this CAWE pattern can be attributed to the low‐pressure system induced by the intensified NEA snow cover, which is further reinforced by the atmospheric wave train generated by negative North Atlantic sea surface temperature anomalies (SSTAs) in winter. This low‐pressure system amplifies the polar vortex and causes cooling in polar regions. Simultaneously, southeasterly winds along the southwestern flank of the North Pacific high‐pressure system contribute to warming in the mid‐latitude regions of Eurasia. While in years when autumn snow cover in TP is less than normal, more snow cover over NEA is accompanied by a ‘warm Arctic‐cold Eurasia’ (WACE) temperature anomaly pattern prevalent during the winter season. The decrease in autumn Barents‐Kara Sea ice is accompanied by a circulation pattern akin to the negative phase of the Arctic Oscillation during winter, favouring the southward intrusion of cold air, thus contributing to this WACE temperature anomaly pattern. Further analysis reveals that the impact of snow cover on the WACE temperature pattern is, for the most part, independent of the Arctic sea ice.
Development of an ex vivo model to study Staphylococcus aureus invasion of the osteocyte lacuno‐canalicular network
Authors: Vanvelk Niels , de Mesy Bentley Karen L. , Verhofstad Michael H. J. , Metsemakers Willem‐Jan , Moriarty Thomas F. , Siverino Claudia
Published: October 2024

Staphylococcus aureus has multiple mechanisms to evade the host's immune system and antibiotic treatment. One such mechanism is the invasion of the osteocyte lacuno‐canalicular network (OLCN), which may be particularly important in recurrence of infection after debridement and antibiotic therapy. The aim of this study was to develop an ex vivo model to facilitate further study of S. aureus invasion of the OLCN and early‐stage testing of antibacterial strategies against bacteria in this niche. The diameter of the canaliculi of non‐infected human, sheep, and mouse bones was measured microscopically on Schmorl's picrothionin stained sections, showing a large overlap in canalicular diameter. S. aureus successfully invaded the OLCN in all species in vitro as revealed by presence in osteocyte lacunae in Brown and Brenn‐stained sections and by scanning electron microscopy. Murine bones were then selected for further experiments, and titanium pins with either a wild‐type or ΔPBP4 mutant S. aureus USA300 were placed trans‐cortically and incubated for 2 weeks in tryptic soy broth. Wild‐type S. aureus readily invaded the osteocyte lacunae in mouse bones while the ΔPBP4 showed a significantly lower invasion of the OLCN (p = 0.0005). Bone specimens were then treated with gentamicin, sitafloxacin, R14 bacteriophages, or left untreated. Gentamicin (p = 0.0027) and sitafloxacin (p = 0.0280) significantly reduced the proportion of S. aureus‐occupied lacunae, whilst bacteriophage treatment had no effect. This study shows that S. aureus is able to invade the OLCN in an ex vivo model. This ex vivo model can be used for future early‐stage studies before proceeding to in vivo studies.
Asymptotic Behavior of Saxion–Axion System in Stringy Quintessence Model
Authors: Seo Min‐Seok
Published: October 2024

The late time behavior of the slow‐roll parameter in the stringy quintessence model is studied when axion as well as saxion are allowed to move. Even though the potential is independent of the axion at tree level, the axion can move through its coupling to the saxion and the background geometry. Then the contributions of the axion kinetic energy to the slow‐roll parameter and the vacuum energy density are not negligible when the slow‐roll approximation does not hold. As the dimension of the field space is doubled, the fixed point at which the time variation of the slow‐roll parameter vanishes is not always stable. It is found that the fixed point in the saxion–axion system is at most partially stable, in particular when the volume modulus and the axio‐dilaton, the essential ingredients of the string compactification, are taken into account. It seems that as more saxion–axion pairs are considered, achieving the stability of the fixed point becomes difficult.
Diatomaceous Earth‐Containing Linseed Oil‐Based Environmentally Friendly Hydrophobic Coatings
Authors: Birtane Hatice
Published: October 2024

The use of bio‐based building blocks for the synthesis of polymers is increasing day by day. Coatings prepared by modifying bio‐based building blocks such as linseed oil (LO) and diatomaceous earth (DE) are very promising. In this study, bio‐based hydrophobic coatings were prepared by cationic photopolymerization technique using epoxidized linseed oil (ELO) and dimer diamine‐modified diatomaceous earth. The bio‐based coatings with hydrophobic properties were prepared by using the spin coating method. ELO was characterized by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H‐NMR). The thermal properties of the prepared coatings were determined by thermogravimetric analysis (TGA). The pendulum hardness, pencil hardness, and gel content of the prepared coatings were examined. Also, the hydrophobicity of the obtained bio‐based coatings was determined by contact angle measurements. The highest contact angle among the investigated compositions was found to be 110°.
Binding of Peptides Containing D‐Amino Acids to the Tsg101 Tumor Susceptibility Protein
Authors: Perez Hugo , Chapagain Prem P. , Gerstman Bernard S.
Published: October 2024

Tsg101 is implicated in tumorigenesis and viral budding, and its inhibition through peptide binding is a potential therapeutic strategy. We utilized the crystal structure of the Tsg101‐PSAP complex from the protein databank in molecular dynamics studies on peptide‐Tsg101 interactions. To enhance peptide stability against enzymatic degradation, we designed peptides with L‐form terminal prolines and D‐form middle amino acids. These peptides also featured acetylated proline at the N‐terminus and amidated C‐terminus, increasing resistance to proteases. Virtual screening of 400 amino acid combinations identified promising peptide candidates and specific binding sites. Subsequent molecular dynamics simulations focused on the peptide PywP, which displayed strong binding stability at a novel Tsg101 site. Further simulations with variations of the D‐form amino acid ′w’ showed that 18 of 21 tested peptides, notably PyeP and PytP, remained firmly bound, highlighting their potential as Tsg101 inhibitors. These peptides also contain hydrophilic residues, potentially improving solubility and therapeutic delivery.
Characterization of Simulated Cytoplasmic Fluids
Authors: El‐Morched Mariam , Barraco Charles , Simionescu Razvan , Harroun Thad , Yan Hongbin
Published: October 2024

Molecularly crowded solutions have been used to simulate cytoplasmic fluids, but little justification is provided in the literature. This work compared three key physical properties of solutions containing polyethylene glycol and sucrose against those in the cytoplasmic fluid from bacteria Escherichia coli: fluid viscosity, relaxation time (T1 and T2) of water, and the diffusion coefficient of water. It was concluded that appropriate mixtures of sucrose and polyethylene glycol 10,000, such as 10% sucrose and 15% PEG10,000 and 7.5% sucrose and 19% PEG10,000, closely mimic these properties of cytoplasmic fluid from E. coli containing around 100 mg/mL of proteins.
Isoniazid Hybrids As Potential Antitubercular Agents
Authors: Mishra Sahil , Kumar Gobind , Singh Parvesh
Published: October 2024

The rapid emergence of various forms of drug‐resistant tuberculosis (TB) has massively impacted people's health globally. According to the WHO, TB care and facilities have been downgraded by 21% since the COVID‐19 pandemic, which has further slowed down the progress toward the “End TB Strategy.” Multiple studies have shown drug‐resistant tuberculosis to be resilient to front‐line antituberculosis drugs, including isoniazid (INH), thus constantly prompting researchers worldwide to probe new potent chemical entities to replace/supplement the current artillery of anti‐TB therapeutics. The molecular hybridization (MH) technique has recently been adopted by many synthetic and medicinal chemists to combine different pharmacophoric units into a single molecular architecture which in most cases has been reported to exhibit a better pharmacological profile as compared to its precursors. The present review provides a concise account of the MH hybridization strategies directed at the structural manipulations of isoniazid to develop new anti‐TB agents and their structure‐activity relationships. Furthermore, their toxicity profiles and docking studies with relevant receptors are also briefly discussed.
Dicationic Methylene‐Bridged Bis(1,2,4‐Triazolium): Construction of Thermally Stable and Insensitive Energetic Salts
Authors: Ji Tianlong , Jiang Xiaoyan , Xiong Jin , Yin Ping , Pang Siping
Published: October 2024

A thermally stable and high nitrogen content energetic cation N,N'‐methylene‐bis(3,4,5‐triamino‐1,2,4‐triazolium) (MTAT, N = 69.38%, ΔHf = 1959.07 kJ/mol) has been used as a building block for preparing a new family of energetic salts. Compounds 1 and 4 were characterized by infrared and multinuclear NMR spectra. Structural confirmation of four salts (1–4) was supported by single‐crystal X‐ray diffraction. Theoretical calculations were performed to calculate the heats of formation and detonation performance using Gaussian 09 and EXPLO5 v6.05 programs, respectively. The impact and friction sensitivity of COMPOUNDS 1 and 2 were measured using BAM standards. Based on experimental and theoretical results, two energetic salts (1 and 3) featuring the novel cation framework MTAT exhibited favorable densities ranging from 1.751 to 1.809 g cm−3 at 298 K, excellent thermal stability (Td: 250–257 °C), acceptable detonation performance (D: 8001–8097 m s−1, P: 23.3–26.7 GPa), and good impact and friction sensitivity (IS: 18–40 J, FS: 240–360 N).
Coumarin‐Tethered‐1,2,3‐Triazoles: Synthesis, Characterization, Antimicrobial Evaluation, and DFT Studies
Authors: Dhawan Sanjeev , Kumar Gobind , Manhas Neha , Mishra Sahil , Jonnalagadda Sreekantha B. , Singh Parvesh
Published: October 2024

A new series of Coumarin‐tethered‐1,2,3‐triazoles (7a–i and 9a–f) were synthesized by the copper‐assisted 1,3‐dipolar cycloaddition reaction of coumarin alkyne (5) with variedly substituted azides (6a–I and 8a–f). All the synthesized compounds were spectroscopically characterized and in vitro antimicrobial testing against a panel of bacterial and fungal strains was systematically carried out. The compounds bearing 3‐Cl (7b) and 2‐NO2 (7i) substituents which emerged as the most potent compounds of the series showed noticeable activity against Staphylococcus aureus. Additionally, density functional theory (DFT) calculations were conducted to explore the chemical reactivity and stability parameters of the compounds.
Hydrogen‐Bonded Cyclic Tetramer Formation of a Pyridylethynylimidazole‐Based Fluorophore
Authors: Miura Youhei , Murai Kazuki , Ando Naoyuki , Yoshioka Naoki
Published: October 2024

Supramolecular have promising application prospects owing to their catalytic, self‐healing, and stimulus‐responsive functions. Pyridylethynylimidazole‐based supramolecular synthons with fluorescent properties have been developed. 4‐(2‐Pyridylethynyl)‐5‐arylethynyl‐1H‐imidazole derivatives 1 with different substituents at the 4‐ and 5‐positions of the imidazole skeleton were prepared using a step‐by‐step Sonogashira coupling reaction. The fluorescence maxima of phenyl‐ and methoxyphenyl‐substituted derivatives 1a and 1c were independent of solvent polarity. On the other hand, ester‐ and cyano‐substituted 1b and 1d showed bathochromically shifted fluorescence maxima in highly polar solvents. In crystals, the 4‐(2‐pyridylethynyl)‐5‐arylethynyl‐1H‐imidazole derivatives formed a supramolecular cyclic tetramer structure via two hydrogen bonds: one was between N─H in imidazole and N in pyridine, and the other was between C─H in imidazole and N in imidazole. Introducing the pyridine ring as a hydrogen bond acceptor, in addition to the imidazole ring, promoted the unique cyclic tetramer structure formation.
Single‐Atom Electron Pumps Over Transition Metal Chalcogenides Boosting Photocatalysis
Authors: Chen Jia‐Qi , Cai Yu‐Shan , Yan Xian , Mo Qiao‐Ling , Yuan Jiao‐Nan , Liu Chu‐Hao , Wu Yue , Xiao Fang‐Xing
Published: October 2024

Cocatalyst is of paramount significance to provide fruitful active sites for suppressing the spatial charge recombination toward boosted photocatalysis. Up to date, exploration of robust and stable cocatalysts is remained challenging. Inspired by the intrinsic merits of single‐atom catalysts (SACs), such as distinctive electronic structure and high atomic utilization efficiency, single‐atom/transition metal chalcogenides (TMCs) is utilized as a model to synthesize CdS‐Pd single‐atom catalyst (CdS‐PdSA) heterostructures. This demonstrates the precise anchoring of isolated metal single‐atom catalysts (SACs) onto TMCs through a simple yet effective wet‐chemical strategy. The resulting heterostructures exhibit significantly enhanced and stable photocatalytic activity for selective anaerobic organic transformations and hydrogen production under visible light. This enhancement is primarily inferred due to the role of Pd SACs as electron pumps, which directionally trap the electrons photoexcited over CdS, accelerating the spatial charge separation and prolonging the carrier lifespan. The charge transport route and photocatalytic mechanism are elucidated. This work underscores the potential of SACs as cocatalysts in heterogeneous photocatalysis, offering valuable insights for the rational design of atomic‐level cocatalysts for solar‐to‐chemical energy conversion and beyond.
Fundamental and Practical Aspects of Break‐In/Conditioning of Proton Exchange Membrane Fuel Cells
Authors: Kostelec Mitja , Gatalo Matija , Hodnik Nejc
Published: October 2024

Proton exchange membrane fuel cells (PEMFCs) have proven to be a promising power source for various applications ranging from portable devices to automotive and stationary power systems. The production of PEMFC involves numerous stages in the value chain, with each stage presenting unique challenges and opportunities to improve the overall performance and durability of the PEMFC stack. These include steps such as manufacturing the key components such as the platinum‐based catalyst, processing these components into the membrane electrode assemblies (MEAs), and stacking the MEAs to ultimately produce a PEMFC stack. However, it is also known that the break‐in or conditioning phase of the stack plays a crucial role in the final performance as well as durability. It involves several key phenomena such as hydration of the membrane, swelling of the ionomer, redistribution of the catalyst and the creation of suitable electrochemical interfaces – establishment of the triple phase boundary. These improve the proton conductivity, the mass transport of reactants and products, the catalytic activity of the electrode and thus the overall efficiency of the FC. The cruciality of break‐in is demonstrated by the improvement in performance, which can even be over 50 % compared to the initial state. The state‐of‐the‐art approach for the break‐in of MEAs involves an electrochemical protocol, such as voltage cycling, using a PEMFC testing station. This method is time‐consuming, equipment‐intensive, and costly. Therefore, new, elegant, and cost‐effective solutions are needed. Nevertheless, the primary aim is to achieve maximum/optimal performance so that it is fully operational and ready for the market. It is therefore essential to better understand and deconvolute these complex mechanisms taking place during break‐in/conditioning. Strategies include controlled humidity and temperature cycling, novel electrode materials and other advanced break‐in methods such as air braking, vacuum activation or steaming. In addition, it is critical to address the challenges associated with standardisation and quantification of protocols to enable interlaboratory comparisons to further advance the field.
The characteristics of sinonasal inverted papilloma and recurrence factors: An analysis of 207 cases
Authors: SamimiArdestani SeyedHadi , Ardehali Mojtaba Mohammadi , Irani Shirin , Firouzifar Mohammadreza , Kazemi Mohammad Ali , Yazdani Farzad , Lotfi Maryam , Jalali Mir Mohammad , Akbarpour Maliheh
Published: October 2024

Objectives

Sinonasal inverted papilloma (IP) is a rare and benign tumor that affects the nose and sinuses. This tumor has a recurring nature and can be associated with malignancy or transform into a malignant lesion. Various factors have been proposed as potential recurrent and malignancy risk factors in sinonasal IP. This study examines some of these factors and the relationship between tumor location and recurrence and malignancy.

Methods

A retrospective analysis was conducted on patients diagnosed with IP for 10 years or more, assessing the patients’ demographic statistics and intraoperative observations. Additionally, CT scan results of the patients were investigated.

Results

Finally, 207 patients with an average age of (52.0 ± 13.8) years were included in the study. A hundred and fifty‐five (74.9%) of patients were male and the most substance abuse was tobacco (72, 34.8%). Fifty‐five (26.6%) patients had a recurrence and 21 (10.2%) patients showed malignancy or dysplastic changes. The most common site of the tumor was the maxillary sinus (131, 63.3%).

Conclusions

Long‐term follow‐up of IP patients is necessary due to the risk of recurrence and malignancy. The probability of recurrence was higher in cases where the tumor involved the frontal sinus or multisite attachment. Therefore, for accurate diagnosis of this tumor and complete resection of the lesion, especially in cases where achieving a free margin may be challenging, the intraoperative frozen section seems necessary.
Room Temperature Phase Transition and Luminescence Behavior of a Novel Metal‐Free Ionic Crystal [C7H16NO][ClO4]
Authors: Shi Xian , Hua Xiu‐Ni , Cai Zhuoer , Zhang Yinan , Zhang Xiang , Huo Pingxin , Li Linjing , Qin Tianshi , Duan Hai‐Bao
Published: October 2024

Metal‐free ionic crystals have attracted tremendous attention for their environmental friendliness, biocompatibility, easy fabrication and structural variability. Herein, a metal‐free ionic crystal [C7H16NO][ClO4] ([C7H16NO]=1‐methyl‐4‐piperidinemethanol) with a dielectric transition at room temperature was designed and constructed. Differential scanning calorimetry (DSC) proved that there exists a reversible phase transition near room temperature at 304 K, accompanied with switchable dielectric behaviors between the low and high dielectric states. The single crystal structure show that the mechanism of such structural phase transition mainly results from the dynamic motion of perchlorate anions. The compound is further shown to exhibit remarkable luminescent properties, characterized by a prolonged lifetime of 18.6 ns. This work offers valuable insights into the construction of room temperature phase‐transition ionic crystals involved with dielectric switching and blue luminescence properties.
Significance of mixed convection and heat transfer flow past a vertical Riga plate in the presence of alumina nanoparticles: Analysis of streamlines for oblique stagnation point
Authors: Li Shuguang , Khan Umair , Zaib Aurang , Ishak Anuar , Lok Yian Yian , Sherif El‐Sayed M.
Published: October 2024

The aim of the current study to inspect the magnetic flow properties and heat transport features near an oblique stagnation point of a nanofluid with mixed convection through a vertical Riga plate are examined. The Riga plate is a familiar actuator made out of permanently fixed electrodes and magnets that moved away from the plate due to an exponential decline in the Lorentz force. Nanofluid is taken into consideration due to its peculiar properties, such as remarkable thermal conductivity is the significance of the study. These properties are important in heat exchangers, electronics, advanced nanotechnology, and material sciences. Using usual similarity transformations, the group of leading partial differential equations is distorted into a group of nonlinear ordinary differential equations. Then, a very proficient procedure namely bvp4c is utilized to discover the solution. For particular values of the different influential fluid parameters, the characteristics of the dimensionless temperature and velocity along with drag force and heat transfer are investigated graphically. In addition, the symmetrical results were initiated for both cases of the slip and without slip parameters. It is demonstrated that for greater influence of the volume fraction of nanoparticles, the normal and tangential velocity profile drops down for the instances of aiding and opposing flows due to fluctuations in the presence of slip factor, and absence of slip factor. In contrast, the temperature profile intensifies in both the cases of slip parameters and without the slip parameter owing to the phenomenon of assisting flow and opposing flow subject to superior impressions of the nanoparticle volume fractions. It is also observed that depending on the equilibrium between buoyancy effects, obliqueness, velocity slip parameters, and straining motion, the location of the point of zero shear stress (friction factor on the surface of the wall) is displaced to the right or the left of the origin.
A fast H3N3‐2σ$_\sigma$‐based compact ADI difference method for time fractional wave equations
Authors: Du Ruilian
Published: October 2024

In the present paper, we derive a fast H3N3‐2‐based compact alternating direction implicit (ADI) scheme for the time fractional wave equation in two‐dimensional spatial domains. The time fractional derivative involved in the equation is discretized by the H3N3‐2 formula combined with sum‐of‐exponential technique. The former was first proposed by Du et al., while the latter has become a widely used technique to reduce the computational cost in the processing of convolution integrals. The spatial discretization adopts the standard compact ADI method, which can ensure that the space can reach the fourth‐order accuracy without increasing the amount of computation. The numerical stability and convergence of the difference scheme are analyzed rigorously. As an auxiliary illustration, a numerical example is given to verify the validity of the theoretical findings.
On the non-measurability of $$\omega $$-categorical Hrushovski constructions
Authors: Marimon Paolo
Published: October 2024

We study $$\omega $$
ω
-categorical MS-measurable structures. Our main result is that a certain class of $$\omega $$
ω
-categorical Hrushovski constructions, supersimple of finite SU-rank is not MS-measurable. These results complement the work of Evans on a conjecture of Macpherson and Elwes. In constrast to Evans’ work, our structures may satisfy independent n-amalgamation for all n. We also prove some general results in the context of $$\omega $$
ω
-categorical MS-measurable structures. Firstly, in these structures, the dimension in the MS-dimension-measure can be chosen to be SU-rank. Secondly, non-forking independence implies a form of probabilistic independence in the measure. The latter follows from more general unpublished results of Hrushovski, but we provide a self-contained proof.
Aspirin in Children; are There Not Two Sides of the Same Coin?
Authors: Schranz Dietmar
Published: October 2024

Dose-dependent in vitro effects of aspirin on platelet inhibition and predictors of non-responsiveness have led to the recommendation of significantly higher doses of aspirin (5 mg/kg/day) in newborns and infants. The results are inconsistent with the pharmacodynamic effects of clopidogrel in newborns, where approximately 30% (0.2 mg/kg/day) of the adult dose (75 mg/day) showed equally effective antiaggregative effects. Consequently, the optimal aspirin dosage remains to be determined. The administration to newborns with congenital heart defects needs to address treatment goals, while accounting for the intricate interactions between platelets and endothelium, as well as the unique aspects of surgical and interventional procedures.
Temperature sensitivity of soil respiration declines with climate warming in subalpine and alpine grassland soils
Authors: Abdalla Khatab , Schierling Larissa , Sun Yue , Schuchardt Max A. , Jentsch Anke , Deola Thomas , Wolff Peter , Kiese Ralf , Lehndorff Eva , Pausch Johanna , Meyer Nele
Published: October 2024

Warming as a climate change phenomenon affects soil organic matter dynamics, especially in high elevation ecosystems. However, our understanding of the controls of soil organic matter mineralization and dynamics remains limited, particularly in alpine (above treeline) and subalpine (below treeline) grassland ecosystems. Here, we investigated how downslope (warming) and upslope (cooling) translocations, in a 5-years reciprocal transplanting experiment, affects soil respiration and its temperature sensitivity (Q10), soil aggregation, and soil organic matter carbon (C) and nitrogen (N) composition (C/N ratio). Downslope translocation of the alpine (2440 m a.s.l.) and subalpine (1850 m a.s.l.) to the lowland site (350 m a.s.l.) resulted in a temperature change during the growing seasons of + 4.4K and + 3.3K, respectively. Warming of alpine soils (+ 4.4K) reduced soil organic carbon (SOC) content by 32%, which was accompanied by a significant decrease of soil macroaggregates. Macroaggregate breakdown induced an increased respiration quotient (qCO2) by 27% following warming of alpine soils. The increase in qCO2 respiration was associated with a significant decrease (from 2.84 ± 0.05 to 2.46 ± 0.05) in Q10, and a change in soil organic matter composition (lower C/N ratios). Cooling did not show the opposite patterns to warming, implying that other mechanisms, such as plant and microbial community shifts and adaptation, were involved. This study highlights the important role of SOC degradability in regulating the temperature response of soil organic matter mineralization. To predict the adverse effect of warming on soil CO2 release and, consequently, its negative feedback on climate change, a comprehensive understanding of the mechanisms of C storage and turnover is needed, especially at high elevations in the Alps that are particularly affected by rising temperatures.
Future aridity and drought risk for traditional and super-intensive olive orchards in Portugal
Authors: Freitas Teresa R. , Santos João A. , Paredes Paula , Fraga Helder
Published: October 2024

Portugal, a leading olive oil producer, boasts six Protected Denomination of Origin (PDO) regions, with distinct olive orchard (OR) densities (traditional rainfed to super-intensive irrigated). This study aimed to assess future drought and aridity conditions and the impacts on ORs located in the PDOs. Therefore, drought and aridity indicators were considered for the historical (ERA5: 1981–2000) and future periods (2041–2060; 2081–2100), and anthropogenic forcing scenarios (RCP4.5 and RCP8.5), using a 7-member ensemble of global climate models. From Spearman’s correlation analysis, Annual Mean Aridity (AIA) was selected as the most representative indicator of the climate conditions, to which the ORs were exposed. Readily Available Soil Water (RAW; mm) was considered to represent the available soil water reservoir for olive trees. Moreover, the Olive Drought and Aridity Risk Index (ODAR) was developed to determine each OR's future risks. This index considered that the AIA and RAW were weighted by OR density fractions. In the future, southern Portugal will be more arid (0.69) than northern and central (0.60). ORs soil shows lower RAW in southern PDOs (< 60 mm) than in central and northern regions (> 90 mm). These results suggest that the south of ORs will be more exposed to water stress than the northern regions. According to ODAR, the ORs exposed to low and high risk will be mainly located in the central parts of the PDOs. In northern ORs, moderate to high risk will predominate. In the south, however, the risk will be very high, which means that the olive tree growth, fruit development, and olive oil quality could be negatively affected. Implementation of tailored adaptation measures will be required to improve the climate resiliency of the sector.
Self-Oscillations of Submerged Liquid Crystal Elastomer Beams Driven by Light and Self-Shadowing
Authors: Norouzikudiani Reza , Teresi Luciano , DeSimone Antonio
Published: October 2024

Liquid Crystal Elastomers (LCEs) are responsive materials that undergo significant, reversible deformations when exposed to external stimuli such as light, heat, and humidity. Light actuation, in particular, offers versatile control over LCE properties, enabling complex deformations. A notable phenomenon in LCEs is self-oscillation under constant illumination. Understanding the physics underlying this dynamic response, and especially the role of interactions with a surrounding fluid medium, is still crucial for optimizing the performance of LCEs. In this study, we have developed a multi-physics fluid-structure interaction model to explore the self-oscillation phenomenon of immersed LCE beams exposed to light. We consider a beam clamped at one end, originally vertical, and exposed to horizontal light rays of constant intensity focused near the fixed edge. Illumination causes the beam to bend towards the light due to a temperature gradient. As the free end of the beam surpasses the horizontal line through the clamp, self-shadowing induces cooling, initiating the self-oscillation phenomenon. The negative feedback resulting from self-shadowing injects energy into the system, with sustained self-oscillations in spite of the energy dissipation in the surrounding fluid. Our investigation involves parametric studies exploring the impact of beam length and light intensity on the amplitude, frequency, and mode of oscillation. Our findings indicate that the self-oscillation initiates above a certain critical light intensity, which is length-dependent. Also, shorter lengths induce oscillations in the beam with the first mode of vibration, while increasing the length changes the elasticity property of the beam and triggers the second mode. Additionally, applying higher light intensity may trigger composite complex modes, while the frequency of oscillation increases with the intensity of the light if the mode of oscillation remains constant.
Oracle-Net for Nonlinear Compressed Sensing in Electrical Impedance Tomography Reconstruction Problems
Authors: Lazzaro Damiana , Morigi Serena , Ratti Luca
Published: October 2024

Sparse recovery principles play an important role in solving many nonlinear ill-posed inverse problems. We investigate a variational framework with learned support estimation for compressed sensing sparse reconstructions, where the available measurements are nonlinear and possibly corrupted by noise. A graph neural network, named Oracle-Net, is proposed to predict the support from the nonlinear measurements and is integrated into a regularized recovery model to enforce sparsity. The derived nonsmooth optimization problem is then efficiently solved through a constrained proximal gradient method. Error bounds on the approximate solution of the proposed Oracle-based optimization are provided in the context of the ill-posed Electrical Impedance Tomography problem (EIT). Numerical solutions of the EIT nonlinear inverse reconstruction problem confirm the potential of the proposed method which improves the reconstruction quality from undersampled measurements, under sparsity assumptions.