bluuebunny/crossref_metadata_2025 huggingface dataset:
The Equivalence Canonical Forms of Two Sets of Five Quaternion Matrices With Applications
Authors: He Zhuo‐Heng , Xu Yun‐Ze , Wang Qing‐Wen , Zhang Chong‐Quan
Published: December 2024

In this paper, the equivalence canonical forms of two sets of five quaternion matrices are considered. The simultaneous decompositions of these two sets of quaternion matrices are established. Some practical algorithms for computing the decompositions are also presented. Using the equivalence canonical forms, some practical solvability conditions for two systems of generalized Sylvester‐type quaternion matrix equations are derived in terms of the ranks of the coefficient matrices. The general solutions to the systems are also provided. Some numerical examples are given to illustrate the results. The proposed simultaneous decompositions are applied to construct a new framework of color watermarks embedding. In this framework, five color watermarks can be embedded into one host image simultaneously with high efficiency. Moreover, a counterexample for the existence of the equivalence canonical form of the general matrix quaternity with the same row or column numbers is presented. The results extend the existing findings on the equivalence canonical forms of general matrix arrays.
Detection of elevated succinate in brain during circulatory arrest in a piglet model: A 3T 1H MR spectroscopy study
Authors: Hurd Ralph E. , Gu Meng , Okamura Kenichi , Shibata Masafumi , Ono Yoshikazu , Haidar Moussa , Riemer R. Kirk , Hanley Frank L. , Spielman Daniel M.
Published: December 2024

Purpose

To measure and validate elevated succinate in brain during circulatory arrest in a piglet model of cardiopulmonary bypass.

Methods

Using data from an archive of 3T 1H MR spectra acquired in previous in‐magnet studies, dynamic plots of succinate, spectral simulations and difference spectra were generated for analysis and validation.

Results

Elevation of succinate during circulatory arrest was observed and validated. Fitting bias was evaluated as a function of the line‐widths and signal‐to‐noise ratios of the archived data. Succinate increases were independent of bypass temperature. Succinate elevation was also not observed with antegrade cerebral perfusion.

Conclusion

Although spectrally overlapped and at sub‐millimolar levels, elevated brain succinate can be reliably measured by dynamic MR spectroscopy at 3T. Noise dependent bias of the stronger overlapping signals did not impact the succinate measurement. Elevated succinate during circulatory arrest and its recovery after reperfusion was observed. This finding is consistent with earlier reports that correlate elevated succinate with ischemic‐reperfusion injury.
Diaphragm Ultrasonography in Patients Without Symptoms or Signs of Respiratory Impairment
Authors: Gorenc Martina , Blagus Rok , Kresal Friderika , Omejec Gregor
Published: December 2024

Introduction/Aims

We aimed to determine differences in diaphragm thickness by including/excluding pleural and peritoneal membranes, the variability in diaphragm thickness over the apposition zone, and the predictors of diaphragm thickness and excursion measurements.

Methods

At least 10 male and female subjects were recruited for each decade of life. Spirometry, respiratory muscle strength, and the diaphragm ultrasound (US) measurements were performed. Multivariate linear regression was applied to determine associations between diaphragm US parameters, subject characteristics, spirometry, and respiratory muscle strength.

Results

In 156 subjects (mean 47.8 ± 17.7; 20–80 years of age), a significant difference in diaphragm thickness was found when comparing measurements that included and excluded the pleural and peritoneal membranes (mean 2.3 vs. 1.7 mm; average difference of 35% (95% CI [15.3–60]); p < 0.001), as well as the minimum and maximum diaphragm thicknesses at different locations over the apposition zone (mean 1.4 vs. 2.1 mm; p < 0.001). Adjusting for sex, age, height, sniff nasal inspiratory pressure, and forced vital capacity, a positive association was found between body mass index (BMI) and diaphragm thickness (β =0.024, p < 0.001, partial R
2 = 0.31, 95% CI [0.018, 0.030]); a negative association was found with the thickening ratio (β = −0.013, p = 0.050, partial R
2 = 0.04, 95% CI [−0.024, −0.002]).

Discussion

Caliper placement and the location of measurement over the apposition zone greatly affect diaphragm thickness, which is also associated with BMI. Therefore, a standardized protocol for measuring diaphragmatic thickness and excursion is desirable, and BMI should be considered when interpreting the results.
Online Learning With Joint State and Model Estimation
Authors: Götte Ricarda‐Samantha , Timmermann Julia
Published: December 2024

Model‐based state observers require high‐quality models to deliver accurate state estimates. However, due to time or cost shortage, modeling simplifications or numerical issues, models often have severe inaccuracies that may lead to insufficient and deficient control. Instead of attempting to iteratively model these deviations, we address the challenge by the concept of joint estimation. Thus, we assume a linear combination of suitable functions to approximate the inaccuracies. The parameters of the linear combination are supposed to be time invariant and augment the model's state. Subsequently, the parameters can be identified simultaneously to the states within the observer. Referring to the principle of Occam's razor, the parameters are claimed to be sparse. Our former work shows that estimating states and model inaccuracies simultaneously by a sparsity promoting unscented Kalman filter yields not only high accuracy but also provides interpretable representations of underlying inaccuracies. Based on this work, our contribution is twofold: First, we apply our approach finally on a real‐world test bench, namely a golf robot. Within the experimental setting, we investigate closed loop behavior as well as how suitable functions need to be chosen to approximate the inaccuracies in a physically interpretable way. Results do not only provide high state estimation accuracy but also meaningful insights into the system's inaccuracies. Second, we discuss and establish a method to automatically adapt and update the model based on collected data of the linear combination during operation. Examining past parameter estimates by principal component analysis, a moving window is utilized to extract the most dominant functions. These are kept characterizing the model inaccuracies, while nondominant functions are automatically neglected and refilled with novel function candidates. After analysis and rebuilding, this updated function set is subsequently fed back into the joint estimation loop and deployed for further estimation. Hence, we give a holistic paradigm of how to analyze and combat model inaccuracies while ensuring high state estimation accuracy. Within this setting, we once more investigate closed loop behavior and yield promising results. In conclusion, we show that the proposed observer provides a helpful tool to guarantee high estimation accuracy for models with severe inaccuracies or for situations with occurring deviations during operation, for example, due to mechanical wear or temperature changes.
Vector‐Valued Nonconforming Finite Element for Surface Flows
Authors: Mehlmann Carolin
Published: December 2024

In the recent years, there has been an increasing interest in the analysis of finite element methods for vector‐valued flow problems on curved geometries. In this contribution, we derive an error analysis for a vector‐valued Crouzeix–Raviart element. The derivation is performed on the vector‐valued Laplace problem, which includes the symmetrical strain rate tensor, an important operator for modeling flow problems. The approximation of the strain rate tensor with the Crouzeix–Raviart element leads to oscillations in the velocity field due to a nontrivial kernel. We derive a stabilized form of the equation and present optimal error bounds in the ‐norm for the Crouzeix–Raviart finite element. The theoretical findings are supported by numerical results.
Shape Sensitivity Analysis of History‐Dependent Materials for Dynamic Structures
Authors: Ghasemi Seyed Ali , Barthold Franz‐Joseph
Published: December 2024

This work presents a sensitivity analysis of inelastic material behavior within dynamic structures. The primary focus is on using the direct differentiation method to derive sensitivity matrices for displacement, velocity, acceleration, and history variables. These methods are validated through a detailed academic example.
A predictive model for electrical conductivity of polymer carbon black nanocomposites
Authors: Abdollahi Fereshteh , Mohammadi Mohsen , Zare Yasser , Munir Muhammad Tajammal , Rhee Kyong Yop , Park Soo‐Jin
Published: December 2024

Although many studies have investigated the percolation threshold and conductivity in the polymer carbon black (CB) nanocomposites (PCBs) by experimental data, the modeling in this field is a topic previously overlooked in literature. This paper suggests a simple equation for percolation threshold in PCBs by the surface properties of polymer and CB a well as interphase depth (t). Also, the electrical conductivity of PCBs is simulated by CB radius (R), tunneling distance (λ) and interphase depth. The offered model is validated by experimented findings of numerous samples and parametric examinations. A thicker interphase and a higher interfacial tension positively reduce the percolation onset. The smaller CBs, lower percolation threshold, and smaller tunnels enhance the electrical conductivity of PCBs. The low percolation threshold of 0.01 is obtained by the low R (15 nm) and the thick interphase (35 nm). Also, R = 15 nm and t = 35 nm maximize the PCB conductivity to 6 S/m. These results signify the important roles of CB radius and interphase depth in the percolation threshold and conductivity of PCBs. In addition, network fraction (f) of 0.7 and λ = 1 nm produce the uppermost PCB conductivity of 1.6 S/m, but the system is insulated at CB network fraction less than 0.35 or tunneling distance more than 2 nm. Therefore, high network fraction and low tunneling distance are needed to enhance the conductivity of PCBs.

Highlights

An equation for percolation onset of PCBs is proposed by CB radius and interphase depth.

The offered model is validated by experimented data and parametric examinations.

A thicker interphase and a higher interfacial tension positively reduce the percolation onset.

Smaller CBs, lower percolation onset, and smaller tunnels enhance the PCB conductivity.

CB radius and interphase depth significantly manage the conductivity of PCBs.
Enhanced microwave absorption and mechanical properties of conformal composite with gradient graphene honeycomb
Authors: Luo Bailu , Liu Yujie , Li YiBin
Published: December 2024

This study aims to develop a novel conformal composite structure with integrated stealth and load bearing. Specifically, the stealth sandwich composite with graphene honeycomb (SCGH) was proposed and used as the electromagnetic (EM) window of overall structure. The multi‐layered honeycomb with gradient impedance was designed and prepared through the chemical self‐assembly process and the vacuum infusion process. The EM reflectivity at different incident angles was experimentally tested to reveal the absorption properties of the SCGH. The measured results show that the SCGH exhibits excellent stealth characteristics. Across the frequency range of 2–18 GHz, the reflection loss (RL) of the SCGH is less than −10 dB. The maximum RL of SCGH is −63 dB at 7.3 GHz. In addition, the SCGH is not very sensitive to the incident angle of EM waves. The uniform loading test was conducted on the overall structure with open window (SOW), and the deformation characteristics and typical damage modes are revealed. The local stiffness of the SOW was reduced by the open window, leading to significant deformation in the window corner areas. The primary damage mode under uniform loading is fiber fracture, occurring at the four window corners due to large deformation. This study provides reference and basis for structural design and performance analysis of conformal composite with integrated stealth and load bearing.

Highlights

Designed and prepared the composite structure with conformal window.

Revealed the stealth performance and reflectivity at different incident angles of structure.

Investigated the mechanical performance and failure mechanism of the structure.
PVDF‐based high‐energy‐storage dielectrics by introducing insulating layer on the surface of metal‐organic frameworks
Authors: Qu Can , Long Yiting , Zhang Xuemei , Liu Jingsong , Pu Linyu , Huang Xu
Published: December 2024

In this paper, UiO‐66 nanoparticles were synthesized through the hydrothermal synthesis technique. Subsequently, a series of metal‐organic framework/polyvinylidene fluoride (MOF/PVDF) composite films were produced via a solution‐casting approach. The dielectric properties of UiO‐66/PVDF (U/P) composite are improved with the addition of UiO‐66. The dielectric constant (ɛr) of 20 wt% U/P composite film at 102 Hz is 11.20, 1.44 times that of pure PVDF film (ɛr = 7.78). However, the breakdown strength (Eb) was only 95 kV mm−1. To solve the problem of sharp decline in Eb, TiO2 with a wide band gap was introduced to form an insulating layer on the surface of UiO‐66. This reduces the difference in electrical properties between the filler and PVDF, hinders the formation of the conductive path within the composite, reduces leakage current, and increases Eb. Compared with the U/P composite, the ɛr and Eb of TiO2@UiO‐66/PVDF (T@U/P) composite film are increased, and the dielectric loss (tanδ) and leakage current density (J) are decreased. The energy storage density (Ue) of 10 wt% T@U/P composite film is 4.51 J cm−3 and the charge and discharge efficiency (η) is 84.61% at 150 kV mm−1. These results indicate that the dielectric properties of UiO‐66 can be significantly enhanced by using titanium dioxide as an insulating layer.

Highlights

By introducing UiO‐66, the ɛr of PVDF material is improved.

Modifying UiO‐66 with TiO2 can improve its breakdown strength significantly.

The Ue of the T@U/P‐10 composite modified with UiO‐66 is 4.51 J cm−3.
Water desalination using CaCO3/blend of polyphenylene oxide and polystyrene mixed matrix membranes in a direct contact membrane distillation (DCMD) unit
Authors: Pakizeh Majid , Rahimnia Rasoul
Published: December 2024

The present study examines the impact of integrating hydrophobic calcium carbonate (CaCO3) nanoparticles into porous membranes composed of a polyphenylene oxide (PPO)/polystyrene (PS) blend on desalination performance. CaCO3 filler was added to polymeric solution at concentrations of 2–10 wt% and prepared samples were characterized using ATR‐FTIR, FE‐SEM, EDX, AFM, liquid entry pressure (LEP), contact angle, and porosity measurement analyzes. Surface porosity of the samples was determined by the Digimizer software. The desalination performance of the membranes was evaluated using a laboratory‐scale direct contact membrane distillation (DCMD) unit. Results showed that nanoparticles did not affect the membrane's finger‐like structure but altered the surface pore size and porosity. Adding 10 wt% CaCO3 to the membrane caused the maximum surface pore size to decrease from 35.4 to 17.4 nm, leading to an increase in the LEP value from 0.9 to 2.1 bar. The MMM with 2 wt% CaCO3 nanoparticles exhibited the highest flux of 34.92 kg/m2h (~20% higher than pure membrane) due to its higher surface porosity, also the rejection was achieved above 99.9%. Physical properties along with thermal efficiency and temperature polarization coefficient of the prepared membranes were compared. Fouling properties and scaling of the prepared membranes were investigated using different organic and inorganic solutions. Results showed that fouling resistance of samples containing CaCO3 filler was improved.

Highlights

Adding hydrophobic CaCO3 to neat polymer, enhanced DCMD performance.

The fouling and scaling resistance of the MMM were better than neat polymer.

MMMs showed a rejection higher than 99.5% due to non‐wetting effect of filler.

Maximum surface porosity and flux was observed for 2.0 wt% of filler loading.

Maximum flux was observed in sample with 2.0 wt% filler loading.
Dynamics of thrombin generation: Filling the gap between the system pharmacology theory and clinical practice in clinical pharmacology and therapeutics
Authors: Ruiz Leire , Jaramillo Sebastian , Calvo Andrea , Torrente M. A. , Tassies Dolors , Reverter J. C. , Blasi Annabel , Troconiz Iñaki
Published: December 2024

Mathematical models of thrombin generation (TG) that have been developed are based on a systems biology approach. Although this approach provides important information about the coagulation system, its clinical applicability is limited by its complexity and number of input variables required. The aim of this study was to develop a semimechanistic model able to describe TG in trauma and control patients. A dataset containing longitudinal data of TG assays and coagulation factors from 40 trauma patients and 20 control patients was used for model building. The model considered three fundamental processes: the degradation of tissue factor (TF) through a first‐order process, the activation of factor II by the TF through a first‐order process, and the degradation of thrombin through a first‐order process. Model fitting was performed using a nonlinear mixed‐effects approach. The condition of the patient (trauma and control) and coagulation factors were modelled as covariates. Model building demonstrated the presence of two additional processes that improved the predictive capacity of the model: the activation of factor II by TF governed by a second‐order constant and, a mechanism of factor II activation by TF characterized by a 7‐compartment transit chain governed by a second‐order constant. In the covariate model only the inclusion of patient condition was significant. Model evaluation demonstrated excellent performance in describing the temporal pattern of TG in trauma and control patients. Thrombin generation can be adequately modelled using a semimechanistic approach. Its application in practice could help to better assess the risk of hemorrhage and/or thrombosis in different settings.
Low‐Temperature Processing to Obtain Contact Resistance of <0.03 Ohm mm to Boron‐Doped Diamond
Authors: Hardy Aaron , Geis Michael W. , Daulton Jeffery W. , Turner George W. , Polking Mark J. , Liddell John , Nebiolo Emily , Myszka Michael , Hollis Mark A. , Ivanov Tony G. , Birdwell A. Glen , Ruzmetov Dmitry , Weil James , Jankowski Nicholas R. , Grotjohn Timothy A. , Zhang Beijia
Published: December 2024

Low‐resistance Ohmic contacts are necessary for high‐performance electronic devices. Ultrawide‐bandgap semiconductor materials typically have high‐resistance Ohmic contacts between the metal contact and the semiconductor. For single‐crystal boron‐doped diamond, with a bandgap of 5.5 eV, the reported specific contact resistance values vary from >10−3 Ω cm2 to the lowest reported value of 2 × 10−7 Ω cm2. To obtain this low‐resistance Ohmic contact, a high temperature, >500 °C, annealing is usually required, which can limit fabrication procedures and compromise device designs. On p‐type single‐crystal diamond, the lowest reported contact resistance is 0.39 Ω mm. This article reports specific contact resistances of 8.2 × 10−8 to 3.6 × 10−7 Ω cm2 and contact resistances 0.027 to 0.041 Ω mm, which are significantly better than reports in the literature and are achieved without the annealing step. The results are achieved by reactive ion etching 10 to 20 nm into the boron‐doped diamond surface. After the etch, evaporated Ti/Au forms Ohmic contacts with resistances between 0.08 and 0.2 Ω mm without an anneal. An additional step of exposing the etched surface to an intense H2 plasma at 700 °C before Ti/Au deposition, results in Ohmic contacts between 0.027 and 0.041 Ω mm.
Scintillation Properties of Ce3+‐Doped Low‐Temperature X1–Y2SiO5 Nanoscintillator Prepared by Polymer‐Assisted Sol–Gel Pathway
Authors: Zahra Billel , Guerbous Lakhdar , Hamroun Mohammed Salah Eddine
Published: December 2024

Herein, three sample detectors are meticulously crafted using cerium‐activated X1–Y2SiO5 (YSO:Ce3+) powder prepared via the monomer and polymer‐assisted sol–gel method. The influence of ethylene glycol (EG) monomer, polyethylene glycol polymer, and polyvinyl alcohol polymer as fuels and nucleating agents on the scintillation properties of Ce3+ (xCe = 0.01)‐doped Y2SiO5 is investigated. The sample detectors are coupled with the XP2020Q photomultiplier tube, and an advanced nuclear instrumentation system is meticulously set up for accurate measurement and characterization of scintillation properties. Scintillation decay time is precisely measured using the delayed coincidence technique under γ‐rays at 662 keV emitted from a 137Cs radioactive source. The findings underscore the significant impact of complexing agents on enhancing the scintillation performance of YSO:Ce3+ nanoscintillators. Notably, the EG‐prepared sample detector exhibits the best performance, with an estimated scintillation light yield of 22 452 ± 2600 ph MeV−1 and a coincidence timing resolution of 480 ps. These results contribute to understanding the synthesis and optimization of YSO:Ce3+ nanoscintillators for various applications, emphasizing the crucial role of the chemical environment in controlling and optimizing scintillation properties.
Finite‐Time Observer Based Prescribed Performance Robust Control for Position Stabilization of Offshore Gangway Ends
Authors: Li Meng , Du Jialu
Published: December 2024

Consider an offshore gangway subject to mathematical model parameter uncertainties and disturbance uncertainties. A finite‐time observer (FTO) is designed to estimate the motion states of the gangway end (GE) and the total uncertain nonlinear disturbances lumped by the parameter uncertainties and disturbance uncertainties. The bandwidth of the FTO is a function of the GE position estimation error and a prescribed performance function and is time‐varying, and thus our designed FTO does not rely on the bounds of the derivatives of the total uncertain nonlinear disturbances compared with conventional FTOs. Whereby, according to the idea of the active disturbance rejection control, we develop a prescribed‐performance robust control law (PPRCL) for GE position stabilization such that the position stabilization error can converge into a prescribed tolerance steady‐state band in a finite settling time. Simulation results with comparisons show the robustness and the advantage of our developed PPRCL.
Charge Dynamic Interface Z‐Scheme on r‐GO–WO3–α‐Fe2O3 Composite Surface for Hydrogen Production
Authors: Haider Rida Shahzadi , Sajjad Shamaila , Leghari Sajjad Ahmed Khan , Khan M. Yaqoob , Shahzad Khurram
Published: December 2024

N‐type thin films of semiconductors WO3, α‐Fe2O3, and nanocomposite structures of WO3–α‐Fe2O3, and WO3–α‐ Fe2O3–r‐GO were prepared on FTO substrates using spray deposition. The optical, morphological, structural, crystallinity, and composition properties were studied by UV–visible spectroscopy, SEM, TEM, XRD, and EDS. Photoelectrochemical efficiency was assessed in a three‐electrode cell assembly and validated through various electrochemical measurements. The improved light absorption capacity of WO3–α‐Fe2O3–r‐GO composites is due to synergistic effect and hierarchical nanostructures with ultrahigh surface areas enhanced by the incorporation of r‐GO. The reduction potentials of WO3 and Fe2O3 can be tuned by controlling morphology and particle size. WO3 as a photoanode suffers from volumetric and structural changes during redox reactions, leading to instability and decreased photocurrent response. Hematite is a promising candidate for PEC water splitting due to its lower bandgap (2.0–2.2 eV) and excellent electrochemical stability in electrolytes. However, it has drawbacks such as low quantum efficiency and short hole diffusion length. The combined benefits of r‐GO, hematite, and WO3 in WO3–α‐Fe2O3–r‐GO composite effectively detect electron dynamics across WO3–α‐Fe2O3 interface with r‐GO serving as a mediator to study charge dynamics at interface. The critical role of r‐GO in enhancing electrochemical performance of nanocomposites has been well established.
Contributing to the Sustainable Development of New Energy Materials: Current Research Status and Future Fate of Conductive Agents for Lithium Iron Phosphate Batteries
Authors: Cui Qingyuan , Wu Huanhuan , Qu Guangfei , Li Junyan , Wu Feihui
Published: December 2024

In the face of the global resource and energy crisis, new energy has become one of the research priorities, and lithium iron phosphate (LFP) batteries are giving rise to a new generation of high‐power lithium‐ion batteries. Carbon‐based materials, as important basic materials, are widely used in various fields with their excellent physicochemical properties, which greatly support the research of dual‐carbon policy. Traditional conductive agents, however, have gradually shown limitations in certain applications of high‐performance lithium‐ion batteries. The development and application of new highly conductive carbon‐based conductive agents has become a mainstream trend in the research of anode conductive agents for lithium‐ion batteries. At present, the conventional conductive agent cannot meet the development needs of high‐performance lithium‐ion batteries. The research and application of new high‐conductivity carbon‐based conductive agents has become the main stream of research and trends in conductive agents for the cathode of lithium‐ion batteries. In this paper, carbon black (CB), carbon nanotubes (CNTs) and graphene are taken as typical materials for carbon‐based conductive agents for LFP batteries as examples, which are individually combined as LFP cathode conductive agents and carbon doped composites, and the synthesis method and action mechanism are discussed. The future research focus on lithium‐ion batteries and new carbon‐based cathode conductors is discussed, providing a reference for the further development of cathode conductors.
Assessing the Interactions in Atmospherically Relevant Sulfuric Acid‐Carboxylic Acid Clusters
Authors: Li Luqi , Xu Jianzhi , Li Ya‐Ke , Hou Gao‐Lei
Published: December 2024

Clusters of atmospheric precursor molecules, like sulfuric acid, bisulfate, and organic carboxylic acids, are important embryos for the formation of aerosol particles, further impacting both the earth radiation budget, cloud formation, and daily life. In this work, we studied theoretically the structures, energetics, and interactions of a cluster formed between HSO4– and acetic acid: HSO4–•H+•CH3COO–, which stands for the uncertain location of the proton, either on HSO4– end or on CH3COO– end. We checked the performance of second‐order Møller–Plesset perturbation theory (MP2) and several density functional theory methods, including BP86, PW91, PBE0, B3LYP, M06‐2X, CAM‐B3LYP, ωB97XD, and B2PLYP with both double‐ζ and triple‐ζ basis sets. We found that overall M06‐2X has good performance for the structures and energetics, and is suggested to be the choice for calculating similar kind of aerosol clusters, but B3LYP also has acceptable performance for optimizing the structures, in particular when dispersion corrections are included. We also found that HSO4–•H+•CH3COO– has two almost energy degenerate hydrogen bonded isomers, that is, HSO4–(CH3COOH) and H2SO4(CH3COO–), and energy decomposition analysis revealed that electrostatic interaction dominates the hydrogen bonding interactions for both isomers, followed by exchange and orbital interactions.
Computational Assessment of Atom Transfer Radical Polymerization in Thermosensitive Poly(Ethylene‐Glycol)‐block‐Poly((2‐(Dimethylamino)Ethyl‐Methacrylate) Copolymer
Authors: Kurniawan Muhammad Arsyik , Salmahaminati Salmahaminati , Kansız Seyithan , Topel Önder
Published: December 2024

Molecular modeling currently plays an important role in chemistry, providing predictions about the structure and properties of chemical compounds in the design and development of new materials. Herein, the thermosensitive block copolymer poly(ethylene‐glycol)‐block‐poly((2‐dimethylamino)ethyl methacrylate) (PEG‐b‐PDMAEMA) was synthesized using atom transfer radical polymerization (ATRP). The structural properties and energy species of the polymer have been evaluated through theoretical studies using density functional theory (DFT). In particular, the electronic properties of the polymers, based on the composition of methacrylate monomers, have been evaluated through the HOMO‐LUMO gap energy, which allows for the description of the global chemical reactivity of the molecules. The electrostatic potential map of the polymer indicates that the oxygen and nitrogen atoms of the PEG‐b‐PDMAEMA polymer are the most effective sites for intermolecular interactions. The nature of interactions in polymer molecules, including steric repulsion, hydrogen bonding, and Van der Waals interactions, was analyzed using the Reduced Density Gradient (RDG) method.
Decoding the Potential of HRAS2 i‐Motif DNA Promoter to Become a Pinpoint Target by Phytomedicine Naringenin
Authors: Bag Sagar , Ghosal Souvik , Bhowmik Sudipta
Published: December 2024

Cytosine‐rich i‐motif (iM) DNA tetraplexes can influence oncogenic transcription and developing phytomedicines for iMs is a viable approach for cancer and other disease treatments. Although natural compounds have been studied as iM binding ligands for anticancer drug discovery, research on the structure‐interaction link between iM and ligand, like the influence of noncoplanar configurations on iM‐ligand binding, is rarely explored. Naringenin (NAR) have gained attention for their potential medicinal properties including high potency and minimal cytotoxicity. Our extensive biophysical and thermodynamic investigations have revealed that NAR interacted preferentially with HRAS2 iM compared to other experimental iMs. This research indicates that it is feasible to regulate gene expression by targeting HRAS2 iM with NAR, which might be beneficial in the development of anticancer medicines. The novel mechanical characteristics of NAR for HRAS2 iM may be important in disease treatments, providing critical insights for the future discovery of drugs with unique therapeutic attributes.
A Focused Review on Oxidation of Hydrazones Using Hypervalent Iodine Reagents
Authors: Sihag Monika , Kinger Mayank , Aneja Deepak Kumar
Published: December 2024

Hydrazones are described as synthetic equivalents to the carbonyl group and possess high synthon value. Herein, we compile the oxidative transformation of hydrazones using ecologically and economically benign hypervalent iodine reagents of the last decade. In this field, the development of C─H functionalization reactions leading to the formation of heterocycles or functionalized hydrazones is a major advancement in recent years. The oxidative properties of hypervalent iodine reagents are exploited to form many bioactive heterocycles (pyrazole, pyrazoline, pyridazine, 1,2,4‐triazole, 1,2,3‐tiazole, 1,3,4‐oxadiazole, tetrazine, tetrazole, pyrrole) through intramolecular or intermolecular C─N, C─O, or N─N coupling. Functionalized heterocycles are also afforded via tandem cascade group transfer/cyclization reactions. The transfer of perfluoroalkyl, sulfoximidoyl, aryl, and halogen groups is achieved using hypervalent iodine reagents as group donors or oxidants in combination with other group‐donating agents. The Togni reagent is the preferred choice for trifluoromethyl group donation, with or without a metal catalyst. Moreover, rearrangement reactions such as acyl migration and the diazotization of hydrazones are also achieved.
Antimicrobial Polymers at the Membrane Interface: Impact of Macromolecular Architecture
Authors: Bapolisi Alain M. , Lehnen Anne‐Catherine , Machatschek Rainhard , Mangiapia Gaetano , Mark Eric , Moulin Jean‐Francois , Wendler Petra , Hall Stephen C. L. , Hartlieb Matthias
Published: December 2024

Antimicrobial resistance (AMR) is a major cause of death worldwide. This urges the search for alternatives to antibiotics, and antimicrobial polymers hold promise due to their reduced susceptibility to AMR. The topology of such macromolecules has a strong impact on their activity, with bottlebrush architectures outperforming their linear counterparts significantly. Consequently, understanding the specific behavior of macromolecules featuring a confined conformation of linear subunits is pertinent. This study focusses on revealing fundamental differences between architectures regarding properties as well as interaction with biological membranes. Various analytical techniques (using membrane mimics and spectroscopic methods) are used to generate insights revealing the following trends: A) The reduction of degrees of freedom in bottle brushes reduces their tendencies for self‐assembly and undesired protein interaction. B) When compared to linear polymers, bottlebrushes attach to membranes faster and more efficiently as well as in a unimolecular fashion. Their multivalent presentation of linear subunits also leads to aggregation between liposomes, which is not induced by linear polymers. C) Neutron reflectometry measurements show an increased tendency of bottle brushes to insert into the hydrophobic tails of phospholipid monolayers. The knowledge about these features will fuel the future development of even more efficient antimicrobial polymers.
Facile Preparation of Carbon Nanotube‐Based Skin‐Like Pressure Sensors
Authors: Yu Xiao , Adronov Alex
Published: December 2024

Flexible sensors have garnered significant interest for their potential to monitor human activities and provide valuable feedback for healthcare purposes. Single‐walled carbon nanotubes (SWNTs) are promising materials for these applications but suffer from issues of poor purity and solubility. Dispersing SWNTs with conjugated polymers (CPs) enhances solution processability, yet the polymer sidechains can insulate the SWNTs, limiting the sensor's operating voltage. This challenge can be addressed by incorporating a self‐immolative linker into the sidechain of a poly(fluorene‐co‐phenylene) polymer, facilitating the fast and clean removal of sidechains and enabling the generation of high‐conductivity SWNT materials. In this work, the integration of this advanced material with polydimethylsiloxane (PDMS) to create skin‐like ultra‐wrinkled film surfaces in a simple, cost‐effective, and highly reproducible manner is demonstrated. The sensors exhibit remarkable sensitivity (1,655 kPa⁻¹) across a wide dynamic range (0.003–70.1 kPa, R2 = 0.9931) when the wrinkle axis is aligned perpendicularly to the interdigitated electrode fingers. The sensor shows an almost instantaneous pressure response and maintains excellent stability. This sensor can monitor various human motions, from low‐intensity activities such as breathing, pulse, and voice vibrations to high‐intensity actions like walking and jumping, highlighting their potential use in wearable human health monitoring systems.
Highly Sensitive Low‐Frequency Acoustic Sensor Based on Functionalized Graphene Oxide
Authors: Chen Anqi , Xi Lin , Li Tianyu , Du Xiaona , Zhang Xiaoyan , Hou Lili
Published: December 2024

Developing miniaturized low‐frequency acoustic sensors with high sensitivity is crucial for diverse applications, including geological monitoring and aerospace exploration. However, the performance of low‐frequency acoustic sensor is constrained by the limited mechanical robustness of traditional sensing films at nanoscale thickness. Here, a functionalized graphene oxide (GO)‐based Fabry‐Perot (FP) low‐frequency sensor is proposed, with characteristics of compact size, resistance to electromagnetic interference high‐sensitivity low minimum detectable pressure (MDP), and a high signal‐to‐noise ratio (SNR). The functionalized GO is synthesized through the reaction of GO with dodecylamine and the uniform film is prepared by a self‐assembly method. This sensor exhibits a sensitivity of −91.92 dB re 1 rad/µPa at 10–200 Hz with a fluctuation of 0.4 dB, ≈5.6 times higher than that of non‐functionalized GO‐based sensors prepared by a direct evaporation method. The MDP of this sensor is determined to be 0.333 µPa/Hz1/2 @20 Hz with a SNR of 136.34 dB, which outperforms previously reported low‐frequency sensors using conventional metals or polymers as sensing films.
Breaking the Ice: Hofmeister Effect‐Inspired Hydrogen Bond Network Reconstruction in Hydrogel Electrolytes for High‐Performance Zinc‐Ion Batteries
Authors: Tan Hao , Meng Chao , Chen Hao , Yang Jia‐Lin , Cao Jun‐Ming , Wu Xing‐Long , Wang Jian‐Jun
Published: December 2024

Gel electrolytes have emerged as a promising solution for enhancing the performance of zinc‐ion batteries (ZIBs), particularly in flexible devices. However, they face challenges such as low‐temperature inefficiency, constrained ionic conductivity, and poor mechanical strength. To address these issues, this study presents a novel PAMCD gel electrolyte with tunable freezing point and mechanical properties for ZIBs, blending the high ionic conductivity of polyacrylamide with the anion interaction capability of β‐cyclodextrin. Leveraging the Hofmeister effect, the chaotropic anions of ClO4− are integrated to weaken hydrogen bonds, enhancing the mechanical and anti‐freezing properties. The chaotropic salt disrupts the hydrogen bond network within water molecules, increasing weaker bonds and forming contact ion pairs, while polyacrylamide chains bind water molecules, further destabilizing hydrogen bonds. These changes improve Zn2+ ion mobility, mechanical resilience, and reduce the freezing point, significantly boosting ZIB performance. Consequently, the Zn‐Zn symmetric cells achieve remarkable lifespans over 5290 hours at 0.5 mA cm−2 and 1960 hours at 5 mA cm−2, and the Zn‐polyaniline full batteries maintain a high capacity of 100.8 mAh g−1 at 2 A g−1, even at −40 °C, over 7600 cycles, showcasing superior cyclability and rate performance.
An isolated intraarticular talar fracture in a dog
Authors: Whybrow Kate , Langley‐Hobbs Sorrel
Published: December 2024

A 3.5‐year‐old, male Hungarian Vizsla was referred for assessment of acute onset non‐weight‐bearing lameness of the right pelvic limb following a trauma involving slipping on the beach. There was no evidence of bony involvement on initial radiographs taken at the primary care practice. On orthopaedic examination, the patient was non‐weight‐bearing lame on the right pelvic limb, had palpable fluid swelling to the right tarsus suggestive of joint effusion, and palpation under sedation demonstrated mild instability of the right tarsocrural joint. Computed tomography revealed an isolated, simple, non‐displaced, oblique, intraarticular talar fracture. The fracture was subsequently stabilised by immobilising the tarsocrural joint with a transarticular external skeletal fixator. Repeated computed tomography (6 weeks after surgery) demonstrated evidence of fracture healing. With further supportive external coaptation, adjunctive physiotherapy and hydrotherapy, the dog made a complete recovery and returned to full function.
Re‐evaluation of the centrifuge method for describing the unsaturated hydraulic functions of porous rock and till soil samples
Authors: Caputo Maria C. , De Carlo Lorenzo , Turturro Antonietta C. , Gerke Horst H.
Published: December 2024

The determination of hydraulic characteristics as a function of the pressure head is laborious and data ranges are restricted. Indirect methods to estimate K(h) are introducing additional uncertainty and the method‐dependent restricted data ranges that can hamper a bimodal curve fitting. The objective of this study was to re‐evaluate the centrifuge approach for directly measuring the unsaturated hydraulic properties of porous carbonate rock and glacial till soil samples. Hydraulic conductivity was determined by means of evaporation (EVA), quasi‐steady centrifuge (QSC), and double‐membrane steady‐through flow (DMSTF) methods. Retention curves were obtained by using the EVA, QSC, mercury intrusion porosimetry (MIP), suction table, and pressure chamber. The tested samples belong to two rock lithotypes coming from the Apulia region, southern Italy, and three soil clods of dense glacial till parent material collected in northeastern Germany. Unimodal and bimodal hydraulic functions were used to fit hydraulic conductivity and retention data. The QSC data of the highly dense soil clods qualitatively demonstrated the different effects of bulk density and rigidity on the soil hydraulic functions. The MIP data showed the existence of a bimodal pore size distribution. The combination of data obtained by EVA, QSC, and DMSTF methods improved the fitting of the bimodal hydraulic conductivity functions to data of both rock and soil samples. The results confirm the uniqueness of the QSC method for measuring the hydraulic conductivity in a wider range of matric potential value and its limitation for nonrigid samples even if they are of high density.
High-Resolution Rainfall Simulations for Early Warning of Rain-Induced Rapid Long-Traveling Landslides in Sri Lanka
Authors: Onishi Ryo , Bandara H. A. A. I. S. , Matsumoto Koki
Published: December 2024

Reliable rainfall prediction is a key for successful early warning of rain-induced long-traveling landslides. This study assesses the rainfall prediction skill of a high-resolution weather prediction model named the Multi-Scale Simulator for the Geoenvironment (MSSG). The rainfall accumulation is more crucial rather than hour-to-hour rainfall intensity for long-traveling landslide. Three heavy rain events, which caused devastating landslide events in Sri Lanka, are chosen for the assessment: (i) Aranayaka in 2016, (ii) Rilpola in 2017 and (iii) Kiribathgala in 2014. The raingaunge observatory data are compared with the 2 km-resolution MSSG simulation and the Global Satellite Precipitation Map (GSMaP) data with approximately 10 km resolution. Comparison results show that the high-resolution MSSG simulation can represent the 3 day and 24 h rainfall accumulations and also the maximum rainfall intensities better than the GSMaP data. In addition to the assessment for rather short-term prediction, we investigate the exceedance probabilities (EPs) of daily maximum of hourly rainfall intensities at two adjacent raingauge points. The EPs show large difference between the mountainous point and plain point even though their separation is just 4.6 km. The 2 km-resolution MSSG simulation can capture the difference in the two EPs. This confirms the MSSG’s reliability in capturing the topographic enhancement of rainfall intensities.
LS-RAPID Estimation of the Critical Pore Pressure Able to Initiate (Activate) Landslides Within the Existing Large-Scale Landslides
Authors: Loi Doan Huy , Van Tien Pham , Dang Khang , Sassa Kyoji
Published: December 2024

Landslides have the potential to cause severe damage to infrastructure and can lead to loss of life. It is crucial to take preventive measures to mitigate landslide risks. Landslides in Sri Lanka are a common natural disaster, often triggered by heavy rainfall during the monsoon season.

The National Building Research Organization of Sri Lanka (NBRO) and the International Consortium on Landslides (ICL) commenced a 5-year research project in 2020 named “Development of Early Warning Technology of Rain-induced Rapid and Long-travelling Landslides (Project RRLL),” which was supported by JICA (Japan International Cooperation Agency) and JST (Japan Science and Technology Agency). The project’s main objective is to create essential technologies for an early warning system that can predict landslides caused by heavy rainfall. One of the key technologies is use of the LS-RAPID to simulate the landslides initiation and motion. First, this article presents two case studies in Japan, and Sri Lanka to show the ability of LS-RAPID to reproduce rainfall-induced landslides. Then, LS-RAPID was applied to estimate the potential activation in previous large-scale landslides and the critical pore pressure needed to initiate landslides in the Aranayake area, Sri Lanka.
MaPLoRds: Mobile Application for Local Road Network Risk Assessment
Authors: Abolmasov Biljana , Stanković Ranka , Vulović Nikola , Marjanović Miloš , Đurić Uroš , Gudžić Nikola
Published: December 2024

MaPLoRds is a software system developed to enable local municipality users to assess the resilience of their local road network from natural hazards in climate-changing conditions. The system analyzes the characteristics of the road network, vulnerability, and climate-related hazards, to evaluate the network’s resilience. A tool for mobile devices (mobile application) is developed to facilitate the data collection in the field and a web application is developed for data analysis, resilience, and priority assessment based on the methodology. The bilingual glossary, in Serbian and English, is produced for the developed version of the application, introducing key terms and phrases that are required for the MaPLoRds interface, both for mobile and web application. The system is developed according to the highest industry standards and by Platform Security and Personal Data Protection rules. Personal Data of the users (e.g., password) are stored in encrypted form in the central database, while all other non-sensitive data are not encrypted. In this paper, the MaPLoRds mobile application is available on https://maplords.rgf.bg.ac.rs
Assessing Landslide Disaster Risk Reduction and Resilience: Case Studies and Insights, India
Authors: Parkash Surya , Singh Ravinder , Badola Shubham
Published: December 2024

The purpose of this paper is to highlight the issues of landslide disaster risk reduction in India by presenting real case studies of landslide incidences happened in the past. It also focuses upon the resilience measures and policies required for reducing landslide risk. This study highlights and give insight on the few important case studies of past landslides/mass-movement incidences such as Phuktal landslide dammed reservoir, Kargil-Ladakh (2015), Idukki-Kerala (2018), landslide at Noney district-Manipur (2022), Rock-ice avalanche and debris flow, Chamoli (2021), land subsidence in Joshimath-Uttarakhand (2022), South Lhonak Glacial Lake Outburst Floods-Sikkim (2023) etc. These disaster events are influenced by the intrinsic factors (i.e., geo-tectonic, drainage/hydrology, land uses) and extrinsic factors (i.e., climate change, anthropogenic activities, climate variability, natural and socio-economic development).

The landslide disaster events induced by geo-tectonics, heavy rainfall, Glacial Lake Outburst Floods (GLOFs), anthropogenic activities etc. have been causing severe losses and damages to lives and properties in different regions of India. The extreme weather events and climate change increases the frequency of disaster events in hilly regions of India. As a result, the necessity for stringent policies and strategies (e.g., landuse, construction practices, enact/revise regulations etc.) for reducing disaster risks was extremely felt. Simultaneously, the advancement of innovative technology and tools such as Deep Learning (DL), data mining, Artificial Intelligence (AI), Machine Learning (ML), Internet of Things (IOT) are required to generate reliable, field validated models of multi-hazards based early warning, risk assessment, mitigation, response etc., which may reduce impacts of future disasters and its occurrences.