bluuebunny/crossref_metadata_2025 huggingface dataset:
Micelle formation of tetradecyltrimethylammonium X‐benzoate surfactants: Benzoate counterion substituent effects
Authors: Bachofer Steven J.
Published: September 2023

Tetradecyltrimethylammonium (TTA+) benzoate surfactants have a range of CMC values dependent on the substituent effects of the benzoate counterions. Twenty‐three TTA+/X‐benzoate CMC values were determined by conductivity and surface tension. The 12 TTA+/para‐ and meta‐benzoate and the unsubstituted benzoate CMC values yield a correlation to the hydrophobicity parameter (log P) of the benzoic acid, as the counterion. The logarithm of conductivity CMCs correlated to the log P value of the benzoic acid yields a slope of—0.4399. All 10 of the TTA+/ortho‐benzoate CMC values do not yield a correlation with hydrophobicity yet the TTA+/ortho‐halogenated benzoates give a strong correlation to hydrophobicity (log P). For this subset, the correlation was nearly identical to one of the TTA+/para‐ and meta‐benzoates. The slope of the logarithm of TTA+/ortho‐halogenated benzoate CMC values to the log P of benzoic acid is—0.413. Another subset is the TTA+/ortho‐hydrogen bond donating benzoates which clearly show micelle formation is favored in addition to the hydrophobic effect. The surface tension data CMCs yield a similar correlation to the conductivity data. This combined data yields further insight on the structural features of the counterion contribution to micelle formation. Specifically, the benzoates show both hydrophobicity effects and when ortho‐hydrogen bond donating substituents are present, micelle formation is strongly enhanced in addition to the hydrophobic effect of the anion.
Seed germination and seedling development assisted by ultrasound: gaps and future research directions
Authors: Nogueira António , Puga Hélder , Gerós Hernâni , Teixeira António
Published: September 2023

Since the early 1930s, when the first corn hybrids were grown commercially, innovations in the agriculture industry have had an unprecedent impact worldwide, helping to meet the demands for food of an exponentially growing population. In particular, seed technology research has contributed substantially to the improvement of crop performance over the years. Ultrasonic treatment of seeds is a green technology that promises to have an impact on the food industry, enhancing germination and seedling development in different species through the stimulation of water and oxygen uptake and seed metabolism. The increase in starch degradation has been associated with the stimulation of the α‐amylases of the endosperm, but relatively few reports focus on how ultrasound affects seed germination at the biochemical and molecular levels. For instance, the picture is still unclear regarding the impact of ultrasound on transcriptional reprogramming in seeds. The purpose of this review is to assess the literature on ultrasound seed treatment accurately and critically, ultimately aiming to encourage new scientific and technological breakthroughs with a real impact on worldwide agricultural production while promoting sustainable practices on biological systems. © 2023 Society of Chemical Industry.
Investigation of some quality properties of yogurt made from cow and sheep milk fortified with folic acid (B9), biotin (B7), and vitamin D3
Authors: Aydemir Mehmet Emin , Altun Serap Kılıç
Published: September 2023

BACKGROUND

The aim of this study was to investigate the effects on some physicochemical properties and starter cultures of yogurts enriched with vitamins at different concentrations during storage. For this purpose, yogurt was produced by adding the vitamins folic acid (B9), biotin (B7), and vitamin D3 in different concentrations to sheep and cow milk and stored at 4 °C. Physicochemical analyses and microbiological analyses were performed for each group of yogurt on days 0, 7, 14, and 21.

RESULTS

There was no significant difference (P > 0.05) between the groups in pH and titration acidity (%) during storage. It was determined that in the yogurts produced from sheep milk, the groups enriched with vitamins had a higher number of L. bulgaricus than the control group on the 7th day of storage. Moreover, the groups containing vitamin D3 exhibited a higher Lactobacillus bulgaricus count on the 21st day of storage. The highest L. bulgaricus counts on the 7th day in yogurts produced from cow's milk were observed in groups containing 0.5 mL of vitamin B9 and B7. No mold or yeast growth was observed during storage in any of the yogurt groups made from cow and sheep milk.

CONCLUSION

In conclusion, it was determined that the enrichment of yogurt with vitamins B7, B9, and D3 did not adversely affect the quality of the yogurt; rather, it improved. We recommend that yogurt enriched with micronutrients be studied economically, and mass production should be initiated by yogurt companies as soon as possible. © 2023 Society of Chemical Industry.
Novel, liquid crystal formula to overcome LTPS LCD image sticking without adjustment of gamma code, optical, VHR and IS evaluation
Authors: Tao Bo‐Cheng , Zhang Wei , Chou Wen‐Chieh , Wang Fangyu , Huang Yapeng , Li Yanan
Published: September 2023

In this article, novel n‐FFS liquid crystal material from Slichem was used in order to elevate the anti‐backlight long aging effect; a trace amount of free radical trap HALS‐like additive was added, the principle of which can be expressed via Denisov cycle, confirmed by measuring the temporal VHR changes in test cells; three different resolution (FHD ~ QHD) models paired with N19 and N21 were selected for testing by comparing the actual panel. It is verified that the optimized material greatly improves the image sticking performance of the panel and keeping optical performance.
Isopropyl‐branched lard and its potential application as a bio‐based lubricant
Authors: Yosief Hailemichael O. , Sarker Majher I. , Bantchev Grigor B. , Dunn Robert O.
Published: September 2023

Regular lard (RL) was chemically modified into isopropyl‐branched lard (BL). The isopropyl group was introduced into the triglyceride structure via a reaction of carbon–carbon double with isopropyl bromide in presence of ethylaluminum sesquichloride. The reaction was confirmed with gas chromatography–mass spectroscopy, nuclear magnetic resonance, infrared spectroscopy. The physical, tribological and chemical properties of the RL, BL and their blendings in polyalphaolefin (PAO) and high‐oleic sunflower oil (HOSuO) were investigated. The BL exhibited better solubility both in HOSuO and PAO than RL. Compared to RL, BL exhibited higher density, viscosity, improved oxidative stability and cold flow properties both as a neat material and blendings in HOSuO or PAO. However, BL displayed lower viscosity index (197 vs. 162) compared to RL. Both RL and BL displayed similar lubricity as HOSuO and showed potential such as a good lubricity additive in PAO even in small amounts (~10 wt%). This study reveals introducing alkyl branching into lard can lead to improved physico‐chemical properties and lubrication performance.
Evaluating organic coating performance by EIS: Correlation between long‐term EIS measurements and corrosion of the metal substrate
Authors: Bongiorno Vincenzo , Michailidou Emmanouela , Curioni Michele
Published: September 2023

In this study, the possibility of obtaining a corrosion indicator from a time series of electrochemical impedance spectra acquired during immersion of intact organic coatings was inspected. To generate a wide distribution in performance, coatings with different pigment volume concentrations were applied on AA2024‐T3 and cold‐rolled mild steel and tested in four different electrolytes and for different exposure times. The relative ranking of anticorrosion performance was based on the visual appearance of the metal substrates after stripping the coating and it correlated well with the estimation of the corrosion charge estimated from the time series of electrochemical impedance spectroscopy spectra.
Data‐driven and artificial intelligence accelerated steel material research and intelligent manufacturing technology
Authors: Geng Xiaoxiao , Wang Feiyang , Wu Hong‐Hui , Wang Shuize , Wu Guilin , Gao Junheng , Zhao Haitao , Zhang Chaolei , Mao Xinping
Published: September 2023

With the development of new information technology, big data technology and artificial intelligence (AI) have accelerated material research and development and industrial manufacturing, which have become the key technology driving a new wave of global technological revolution and industrial transformation. This review introduces the data resources and databases related to steel materials. It then examines the fundamental strategies and applications of machine learning (ML) in the design and discovery of steel materials, including ML models based on experimental data, industrial manufacturing data, and simulation data, respectively. Given the advancements in big data, AI/ML, and new communication technologies, an intelligent manufacturing mode featuring digital twins is deemed critical in guiding the next industrial revolution. Consequently, the application of intelligence manufacturing with digital twins in the iron and steel industry is reviewed and discussed. Furthermore, the applications of ML in service performance prediction of steel products are addressed. Finally, the future development trends for data‐driven and AI approaches throughout the entire life cycle of steel materials are prospected. Overall, this work presents an in‐depth examination of the integration of data‐driven and AI technologies in the steel industry, highlighting their potential and future directions.
Radial and nonradial solutions for nonautonomous Kirchhoff problems
Authors: Zhang Jing , Liu Jianming , Qin Dongdong , Wu Qingfang
Published: September 2023

In this paper, we study the following nonautonomous Kirchhoff problem:

where
,
,
,
is a positive constant,
is a parameter, and the potential functions
belong to
. The existence of radially symmetric and positive solution to the above problem is first established for all
when
are radially symmetric and
, and the range of
can be extended to
with the aid of a coercive type assumption on
. Moreover, we show the existence of infinitely many solutions with high energies via the fountain theorem under more general assumption on
which allows it to be sign‐changing. When
and
, we show that the above problem possesses infinitely many solutions with negative critical values for small
provided that the function
belongs to a suitable space. In particular, by imposing a hypothesis on the potential
controlling its growth at infinity, we obtain a nonradial solution via the mountain pass theorem and the principle of symmetric criticality.
Grand and small norms in Lebesgue spaces
Authors: Berezhnoi Evgeny , Karapetyants Alexey
Published: September 2023

We present a new approach to the definition of grand and small Lebesgue spaces. This in particular allows to include into consideration the extreme exponents
and
. Basically, the study of the extreme exponent case is the main result of the article. However, we expect that our general construction for the norms in grand and small Lebesgue spaces will imply further studies of the spaces and operators in these spaces in such a general setting.
J‐filter: An experiment to simplify and isolate specific signals in 1H NMR spectra of complex mixtures based on scalar coupling constants
Authors: Góñez Karen V. , García Juan Suárez , Sardina F. Javier , Pazos Yolanda , Saá Ángela , Martín−Pastor Manuel
Published: September 2023

One‐dimensional selective NMR experiments relying on a J‐filter element are proposed to isolate specific signals in crowded 1H spectral regions. The J‐filter allows the edition or filtering of signals in a region of interest of the spectrum by exploiting the specific values of their 1H‐1H coupling constants and certain parameters of protons coupled to them that appear in less congested parts of the spectrum (chemical shifts and coupling constants). The new experiments permitted the isolation of specific peaks of phytosterol components in a sample obtained from a liquid nutraceutical recommended for lowering blood cholesterol levels in regions with complete overlap in the 1H spectrum.
Stage‐parallel preconditioners for implicit Runge–Kutta methods of arbitrarily high order, linear problems
Authors: Axelsson Owe , Dravins Ivo , Neytcheva Maya
Published: September 2023

Fully implicit Runge–Kutta methods offer the possibility to use high order accurate time discretization to match space discretization accuracy, an issue of significant importance for many large scale problems of current interest, where we may have fine space resolution with many millions of spatial degrees of freedom and long time intervals. In this work, we consider strongly A‐stable implicit Runge–Kutta methods of arbitrary order of accuracy, based on Radau quadratures. For the arising large algebraic systems we introduce efficient preconditioners, that (1) use only real arithmetic, (2) demonstrate robustness with respect to problem and discretization parameters, and (3) allow for fully stage‐parallel solution. The preconditioners are based on the observation that the lower‐triangular part of the coefficient matrices in the Butcher tableau has larger in magnitude values, compared to the corresponding strictly upper‐triangular part. We analyze the spectrum of the corresponding preconditioned systems and illustrate their performance with numerical experiments. Even though the observation has been made some time ago, its impact on constructing stage‐parallel preconditioners has not yet been done and its systematic study constitutes the novelty of this article.
An LBB‐stable P1/RNP0 finite element based on a pseudo‐random integration method for incompressible and nearly incompressible material flows
Authors: Feulvarch Eric , Brosse Alexandre , Vincent Yannick
Published: September 2023

The aim of this work is to propose a new nodal treatment of the pressure for tetrahedral or triangular meshes devoted to the simulation of incompressible and nearly incompressible material flows. The approach proposed has the interest of fulfilling numerically the LBB condition for P1‐type discretizations over a wide range of element sizes. Thus, the existence of an error estimate is ensured and there is no need for a stabilization technique. For more convenience, the new P1/RNP0 formulation is first detailed for the Stokes problem. It is based on a RNP0 (Random Nodal P0) approximation of the pressure with constant values on nodal subcells whose size is defined by means of a pseudo‐random number generator. For nearly incompressible material flows, the numerical approach is extended to problems involving von Mises elasto‐plasticity. Examples are presented to show the relevance of the new approach for Eulerian and Lagrangian formalisms.
Failure Patterns Within Different Histological Types in Sinonasal Malignancies: Making the Complex Simple
Authors: Liu Qian , Sun Meng , Wang Zekun , Qu Yuan , Zhang Jianghu , Wang Kai , Wu Runye , Zhang Ye , Huang Xiaodong , Chen Xuesong , Wang Jingbo , Xiao Jianping , Yi Junlin , Xu Guozhen , Luo Jingwei
Published: September 2023

Objective

To analyze the failure patterns in patients with different histological subtypes of sinonasal malignancies (SNMs).

Study Design

Retrospectively gathered data.

Setting

Academic university hospital.

Methods

Patients with SNMs treated at a tertiary referral center between January 1999 and January 2019 were included. We assessed the failure patterns within different histological subtypes.

Results

The study included 897 patients. The median follow‐up time was 100 months. Adenoid cystic carcinoma (ACC) had a moderate risk of developing local recurrence (LR) and distant metastasis (DM). Compared with ACC, squamous cell carcinoma (SCC), adenocarcinoma (AC), soft tissue sarcoma (STS), and mucosal melanoma (MM) were classified as a high LR risk group. For DM, neuroendocrine carcinoma (NEC), STS, and MM were in the high‐risk group.

Conclusions

ACC had intermediate local and distant failure risks, while SCC, AC, STS, and MM were at high LR risks. NEC, STS, and MM were at high DM risk.
The Role of the Otolaryngologist in Sexual Health
Authors: Haugen Thorsen , Pichardo Priscilla , Hellums Ryan , Lindemann Logan , Altman Kenneth
Published: September 2023

Sexual health is an often neglected topic in otolaryngology. Ironically, most sexually transmitted diseases (STDs) demonstrate head and neck manifestations. Furthermore, many aspects of human sexuality, both pathologic and nonpathologic, are also integral to the head and neck. The human papillomavirus (HPV) serves as a prime example of the otolaryngologist's increasingly important role. In recent decades, HPV‐mediated head and neck cancer has surpassed HPV‐mediated cancer in other parts of the body. This dramatic rise has led to not only a change in the staging system, but also a fundamental shift in the treatment paradigm. Similarly, when considering all aspects of sexual health pertaining to the head and neck, a comparable paradigm shift is needed due to the changing needs of our patients. To accomplish this, otolaryngologists must be better educated and take a leading role when it comes to sexual health.
Importance of PET/CT in Initial Workup of Head and Neck Squamous Cell Carcinoma
Authors: Hellums Ryan N. , Pichardo Priscilla F. A. , Altman Kenneth W. , Penn Ellen , Stavrides Kevin P. , Purdy Nicholas C.
Published: September 2023

Objective

Assess the impact of positron emission tomography/computed tomography (PET/CT) on disease staging at presentation in patients with head and neck squamous cell carcinoma.

Study Design

Retrospective cross‐sectional review.

Setting

Academic multicenter single institution (Geisinger Health System).

Methods

All patients who had PET/CT imaging during workup for head and neck squamous cell carcinoma were included in the study. Pre‐ and post‐PET/CT clinical staging were recorded. Statistical analyses were performed for patients with a change in clinical staging or detection of second primary malignancies on PET/CT.

Results

A total of 292 patients were included in the study, 238 of whom underwent PET/CT imaging as part of their initial workup. Twenty‐eight (11.9%) patients were clinically upstaged on PET/CT with 7 patients having treatment alterations based on imaging. Eighteen (7.6%) patients were found to have second primary malignancies on PET/CT.

Conclusion

The current study further illustrates the importance of PET/CT in the workup of head and neck squamous cell carcinoma. Without the inclusion of PET/CT imaging, 19.3% of patients would have either been staged inappropriately or had second primary malignancies missed, again confirming the necessity of comprehensive functional imaging during the initial pretreatment workup.
Model order reduction methods applied to neural network training
Authors: Freitag M.A. , Nicolaus J.M. , Redmann M.
Published: September 2023

Neural networks have emerged as powerful and versatile tools in the field of deep learning. As the complexity of the task increases, so do size and architectural complexity of the network, causing compression techniques to become a focus of current research. Parameter truncation can provide a significant reduction in memory and computational complexity. Originating from a model order reduction framework, the Discrete Empirical Interpolation Method is applied to the gradient descent training of neural networks and analyze for important parameters. The approach for various state‐of‐the‐art neural networks is compared to established truncation methods. Further metrics like L2 and Cross‐Entropy Loss, as well as accuracy and compression rate are reported.
Introduction to the numerical flow iteration for the Vlasov–Poisson equation
Authors: Wilhelm Rostislav‐Paul , Kirchhart Matthias , Torrilhon Manuel
Published: September 2023

We present a novel approach to solve the Vlasov–Poisson equation: the numerical flow iteration. It evaluates the numerical solution by storing the low‐dimensional electric potentials and uses these to iteratively reconstruct the characteristics. This reduces the total memory footprint by several orders of magnitude as complexity gets shifted from memory access to computation on‐the‐fly. Furthermore, this ansatz yields strong conservation properties due to the exploitation of the solution structure.
Surface Crouzeix‐Raviart element for the Bochner Laplacian equation
Authors: Mehlmann Carolin
Published: September 2023

Recently, a nonconforming finite element method has been derived for vector valued flow problems on the sphere. In the approach, the flow is approximated via edge integration through the Crouzeix‐Raviart element. The discretization is realized on local flat triangles which coincide with the surface of the sphere on the edge midpoints. In this contribution, we derive an energy error estimate for this discretization that takes into account the geometric error as well as the error to the solution of the partial differential equation. The analysis is performed for a vector Laplace problem which includes covariant derivatives of tangential vector fields. The latter are closely related to operators that occur in flow problems on the surface.
Mixed‐integer NMPC for real‐time supervisory energy management control in residential buildings
Authors: Bitner Dimitri , Burda Artyom , Grotjahn Martin , Kirches Christian , Schild Axel , Luck Bennet
Published: September 2023

In recent years, building energy supply and distribution systems have become more complex, with an increasing number of energy generators, stores, flows, and possible combinations of operating modes. This poses challenges for supervisory control, especially when balancing the conflicting goals of maximizing comfort while minimizing costs and emissions to contribute to global climate protection objectives. Mixed‐integer nonlinear model predictive control is a promising approach for intelligent real‐time control that is able to properly address the specific characteristics and restrictions of building energy systems. We present a strategy that utilizes a decomposition approach, combining partial outer convexification with the Switch‐Cost Aware Rounding procedure to handle switching behavior and operating time constraints of building components in real‐time. The efficacy is demonstrated through practical applications in a single‐family home with a combined heat and power unit and in a multi‐family apartment complex with 18 residential units. Simulation studies show high correspondence to globally optimal solutions with significant cost savings potential of around 19%.
On dynamic crack propagation in a lattice Boltzmann method for elastodynamics in 2D
Authors: Müller Henning , Schlüter Alexander , Faust Erik , Müller Ralf
Published: September 2023

In recent years, the development of lattice Boltzmann methods (LBMs) for solids has gained attention. Fracture mechanics as a viable application for these methods has been presented before, albeit for mode III cracks in the context of an LBM for antiplane shear deformation. The performance of the LBM itself is promising, while the usage of a regular lattice simplifies the modelling of fractures significantly. Recent advancements in LBMs for solids, especially the description of Dirichlet‐ and Neumann‐type boundary conditions, now make it possible to extend the LBM simulation of crack propagation to the plane strain case with modes I and II crack opening, including growth with non‐uniform speed in arbitrary directions. For this, the configurational force acting on a crack tip is utilised. The definition of the moments of the LBM, which are based on the balance laws of continuum mechanics, render the evaluation of macroscopic fields in the configuration straightforward. In this work, the general in‐plane case of dynamic crack propagation is shown and necessary considerations for the implementation are discussed. Lastly, numerical examples showcase the capabilities of the proposed method to model dynamic fractures and establish a proof‐of‐concept.
Computational modeling of fracture in polymer nano‐composites undergoing large deformations via the graded‐interphase‐enhanced phase‐field fracture approach
Authors: Kumar Paras , Mergheim Julia
Published: September 2023

The phenomenon of fracture in polymer composites, polymer nano‐composites in particular, entails a multitude of intricate mechanisms including branching and merging of several cracks along with particle debonding and subsequent plastic void growth. This work involves an extension of the standard phase‐field fracture approach by means of the graded interphase concept in order to facilitate the modeling of a wide‐spectrum of fracture responses, which can be observed in experimental studies concerning the fracture behavior of polymer nano‐composites. Herein, motivated by the microstructure morphology of polymer nano‐composites, a continuous grading of the elastic and fracture properties is considered within a finite thickness interphase region around the filler particles. Appropriate tuning of the graded‐interphase model parameters enables to capture a variety of fracture responses, including cohesive failure between the filler particle and the matrix, as demonstrated via the presented numerical examples, which focus on polymer nano‐composites undergoing large deformations prior to fracture.
Toward coupled fire‐structure simulations for forecasting smoke leakage in case of concrete structures under fire
Authors: Palani A. , Kandekar C. , Breuer M. , Weber W. E.
Published: September 2023

Computational modeling of the fire‐structure interaction demands the coupling between several models typically implemented in independent simulation software describing distinct physical processes. For instance, in the event of a fire breakout or building on fire, the fire not only increases the temperature of the immediate area but also initiates structural damage, leading to the spalling of the concrete along with the propagation of the smoke, heat, and radiation originating from the fire. As a result of the progressive structural damage caused by the fire such as macro cracks or breakthroughs in the wall, smoke and other hazardous gases begin to disperse and spread into previously unaffected zones. Thus, it represents a coupled multi‐physics problem, which is not well addressed in the scientific community, yet. Therefore, the investigation of such fire‐structure interactions requires a comprehensive computational modeling and simulation framework that couples the consequences of various phenomena with minimal invasive solver modifications. In this work, the structural model treats concrete as a multi‐phase porous material exposed to high temperatures resulting from the fire. For this purpose, the structural solver is at the moment manually coupled with a computational fluid dynamics (CFD) solver to setup a computational framework for such fire‐structure simulations. Herein, the combustion process of the fire and the smoke propagation is carried out using the open‐source software denoted as Fire Dynamics Simulator (FDS) and the thermo–hydro–mechanical fracture is computed using a FEniCS‐based solver. The finite‐difference method based FDS solves the filtered Navier–Stokes equations using the large‐eddy simulation technique to describe the turbulent flow and heat transfer including radiation and combustion inside the fluid domain. The concrete damage such as cracks, holes, or spalling is computed using a phase‐field method in a separate solver based on the thermal boundary conditions from the fire simulation. Subsequently, both solvers are coupled using the open‐source coupling framework preCICE. Based on the rate at which the crack or spalling is developing, the computational domain of the fluid solver has to be adapted taking the generated holes in the wall structure into account for the ongoing CFD simulation. It allows for the leakage of smoke gases through the concrete wall structure and thus the spreading of the fire scenario. The proposed model is illustrated by an exemplary case that forecasts the leakage of smoke and hazardous gases from the successive damage caused by the thermal spalling induced on a concrete wall structure.
Bottom‐up analysis framework for the continuous multidirectional carbon fiber‐reinforced PEEK composite laminates
Authors: Ma Xiaolong , Wen Lihua , Xiao Jinyou , Wang Shiyu , Lei Ming
Published: September 2023

The continuous carbon fiber‐reinforced polyether ether ketone (CCF/PEEK) composites have been widely utilized in aerospace structures due to their excellent properties. However, the main load‐bearing structure in the next‐generation aircraft needs to withstand high temperatures up to 200°C, and the mechanical properties of CCF/PEEK composites show significant time‐/temperature‐dependence due to the viscoelastic nature of the PEEK matrix. Therefore, accurate predictions of the mechanical performance of CCF/PEEK composites under high‐temperature service conditions are the key issue for structural safety and life assessments and have therefore become a recent research focus. To address these challenges, this study established a bottom‐up analysis framework for the CCF/PEEK composites and employed the theoretical model and the finite‐element representative volume element (FE‐RVE) method to investigate the anisotropic viscoelastic properties of CCF/PEEK composites. We first built an anisotropic viscoelastic model of the unidirectional CCF/PEEK composites by integrating the generalized Maxwell into the bridging model. Upon this foundation, we further developed a viscoelastic laminate model capable of accurately predicting the thermoviscoelastic properties of multidirectional laminates. To verify the developed model, different kinds of FE‐RVEs were built and analyzed. Overall, there is good agreement among the model predictions, the FE‐RVE simulations, and the experimental results within a temperature range of 25–250°C. The developed model can be used to design the high‐temperature performance of CCF/PEEK composites with different fiber volume fractions, laminated configurations, or loading directions.

Highlights

An anisotropic viscoelastic model of the unidirectional (UD) continuous carbon fiber‐reinforced polyether ether ketone (CCF/PEEK) composites is built.

The viscoelastic laminate composite model is developed based on the UD CCF/PEEK composites model.

The finite element representative volume element (FE‐RVE) simulation with fibers in a hexagonal or random array has better accuracy compared with the experimental results.

The FE‐RVE simulation and the experimental results verified the developed model from 25°C to 250°C.
Comprehensive quality control of Qingjin Yiqi granule based on UHPLC‐Q‐Orbitrap‐MS and UPLC‐QQQ‐MS
Authors: Zhang Yuxin , She Lihe , Ding Hui , Chen Biying , Fu Zhifei , Wang Liming , Zhang Tao , Han Lifeng
Published: September 2023

Introduction

Qingjin Yiqi granule (QYG) is a prescription medicine of traditional Chinese medicine which is widely used clinically for the recovery of coronavirus patients. However, there is currently limited research on the quality control of QYG.

Objective

To evaluate the quality of QYG qualitatively and quantitatively by making full use of advanced chromatography–mass spectrometry techniques.

Methods

Firstly, a multicomponent characterisation of QYG was performed by ultrahigh‐performance liquid chromatography coupled with a Q Exactive™ hybrid quadrupole‐Orbitrap mass spectrometry (UHPLC‐Q‐Orbitrap‐MS) system using a rapid negative/positive switching mode. Secondly, the co‐condition fingerprint analysis of constituted herbal medicines of QYG was performed to unveil active ingredients as the quality markers of QYG. Thirdly, the marker compounds in 10 batches of QYG were quantified by ultrahigh‐performance liquid chromatography coupled with a Waters Xevo TQ‐S triple quadrupole mass spectrometry (UPLC‐QQQ‐MS) system.

Results

A comprehensive method that combined the inclusion list and data‐dependent acquisition (DDA) to achieve a systematic characterisation of QYG was established by UHPLC‐Q‐Orbitrap‐MS. After analysis based on Compound Discoverer software and Global Natural Products Social (GNPS) platform, a total of 332 compounds were detected. Eleven Q‐markers were determined for the quality evaluation of QYG by comparison with the fingerprint of nine constituted herbal medicines. An adjusted multiple reaction monitoring (MRM) quantification method was further established to simultaneously determine the 11 Q‐markers for holistic quality evaluation of QYG.

Conclusion

This is the first study to report comprehensive multicomponent characterisation, identification, and quality assessment of QYG, which could be used for effective guarantee of the quality of QYG.
Occurrence of sleep‐disordered breathing in children with pulmonary hypertension
Authors: Ignatiuk Daniel , Miles Kimberley , Gurbani Neepa , Hossain Md Monir , Cash Michelle , Magness Melissa , Hirsch Russel , Simakajornboon Narong
Published: September 2023

Background

Obstructive sleep apnea (OSA) has been associated with pulmonary hypertension (PH) through a complex and bidirectional relationship. The prevalence of OSA and other forms of sleep‐disordered breathing (SDB) among children with PH is not well understood. A better understanding could help elucidate contributing factors for PH, guide diagnostic testing, and inform therapies. We therefore determined the proportion of SDB codiagnosis and OSA risk factors among a cohort of children with PH.

Methods

Retrospective chart review was performed for children 0−21 years old with PH who underwent polysomnography (PSG) between 1 January 2010 and 31 August 2020. The primary outcome was OSA occurrence and risk based on demographics, diagnoses, and PH classification. The secondary outcome was occurrence and risk of other SDB diagnoses based on PH classification.

Results

Among 89 children identified, diagnoses included OSA (N = 79, 89%), central sleep apnea (N = 11, 12%), sleep‐related hypoventilation (N = 6, 7%), and non‐apneic hypoxemia (N = 28, 31%). Trisomy 21 diagnosis (N = 38, 43%) was associated with increased OSA risk (RR: 1.24, 95% CI: [1.09−1.42]) and age >12 months at PSG was associated with decreased OSA risk (N = 52, 58%, RR: 0.60, 95% CI: [0.45−0.81]). There was no difference in SDB risk based on Group 1 (N = 56, 63%) or Group 3 (N = 33, 37%) PH and no difference in OSA severity based on demographics and diagnoses.

Conclusion

OSA was diagnosed among a majority of children with PH, and other SDB diagnoses were identified in a significant proportion of children. These findings support routine screening for SDB with PSG in children with PH.
Chinese clinical practice guidelines for the prevention and treatment of radiation‐induced esophagitis
Authors: Yang Congrong , Wang Jun , Yuan Shuanghu
Published: September 2023

Acute radiation‐induced esophagitis is a common complication of radiotherapy for esophageal, lung, and other malignancies. Therefore, understanding the diagnosis, grading, risk factors, prevention, and treatment of radiation‐induced esophagitis is essential. Currently, there are few consensuses and guidelines on radiation‐induced esophagitis worldwide, mainly the American College of Gastroenterology (ACG) clinical guideline: evidenced based approach to the diagnosis and management of esophageal eosinophilia and eosinophilic esophagitis (EoE) and the Digestive Endoscopy Society of Chinese Medical Association's “Guidelines for the Diagnosis and Treatment of Reflux Esophagitis.” However, no consensus or guidelines specifically addressing radiation‐induced esophagitis have been established. Efforts have been made to organize experts to draft Chinese consensus or guidelines, but the recommendations in these guidelines also vary owing to differences in expert backgrounds. The clinical practice guidelines presented herein were developed for the first time with the joint participation of Chinese radiotherapy experts. Drugs and methods with clinical significance were selected by reviewing and summarizing the prevention and treatment of radiation‐induced esophagitis and combining them with China's national conditions. After multiple rounds of discussion and revision, clinical practice guidelines were established in line with the needs of Chinese clinicians, providing useful clinical guidance for the prevention and treatment of radiation‐induced esophagitis.
Cutaneous reactions secondary to COVID‐19 vaccination
Authors: Jmor Shilan , Yip Vincent
Published: September 2023

Cutaneous reactions reported following COVID‐19 vaccination range from mild, self‐limiting reactions to much rarer life‐threatening conditions. This article discusses how to recognise these different types of reaction and determine causality, and provides guidance on the benefits and risks of further vaccination.
A novel iterative learning control method for longitudinal trajectory tracking of aerospace vehicles
Authors: Cheng Zhongtao , Fu Wenze , Liu Lei , Wang Bo , Wang Yongji
Published: September 2023

Considering the precise model information of the aerospace model is not always available under the effect of external disturbance and model uncertainty, a new data‐driven point‐to‐point iterative learning control (PTPILC) method is proposed for aerospace vehicles to track the predetermined trajectory. Firstly, the system of the aerospace vehicle is converted into a discrete form without any omission, which reflects the dynamics of the original system by input and output data. Then, the objective function of the tracking error is proposed in the quadratic form to facilitate the application of the conjugate gradient algorithm, which develops an improved data‐driven PTPILC method. And the convergence analysis of the proposed method is presented. Furthermore, the control parameters are optimized to make the proposed method more robust against different parameter deviations. Finally, the effectiveness of the proposed method is illustrated by different simulations.
Attaining sustainable business performance under resource constraints: Insights from an emerging economy
Authors: Abid Nabila , Ceci Federica , Aftab Junaid
Published: September 2023

Rapid economic growth, intense competition, and rising environmental concerns are compelling businesses to attain sustainable performance and preserve long‐run interests. Considering the lack of EO in small and medium enterprises (SMEs) in the emerging context of Pakistan, the present study investigates the impact of entrepreneurial orientation (EO) on sustainable business performance (economic, environmental, and social) by drawing perspective from dynamic capabilities and resource‐based views. The mediating role of innovation capabilities between EO‐sustainable performance and the moderating effect of technology dynamism on the EO‐innovation capabilities link is also examined. Data from 408 Pakistani SMEs was analyzed using the structural equation modeling. The findings reveal a direct positive influence of EO on sustainable performance. Furthermore, innovation capabilities are found to mediate the EO‐sustainable performance relationship, while technology dynamism positively moderates the EO‐innovation capabilities link. These results emphasize the importance of aligning EO with innovation capabilities to adapt to technological changes in the industrial regime. The theoretical contributions emphasize the importance of promoting EO‐innovation capabilities. Practical contributions imply that entrepreneurs should create an enabling environment that fosters innovation capabilities within SMEs to enhance sustainable performance, especially in resource‐constrained emerging settings. The study also offers researchers a foundation for further investigations in this area.
Addressing missing data in the estimation of time‐varying treatments in comparative effectiveness research
Authors: Segura‐Buisan Juan , Leyrat Clemence , Gomes Manuel
Published: September 2023

Comparative effectiveness research is often concerned with evaluating treatment strategies sustained over time, that is, time‐varying treatments. Inverse probability weighting (IPW) is often used to address the time‐varying confounding by re‐weighting the sample according to the probability of treatment receipt at each time point. IPW can also be used to address any missing data by re‐weighting individuals according to the probability of observing the data. The combination of these two distinct sets of weights may lead to inefficient estimates of treatment effects due to potentially highly variable total weights. Alternatively, multiple imputation (MI) can be used to address the missing data by replacing each missing observation with a set of plausible values drawn from the posterior predictive distribution of the missing data given the observed data. Recent studies have compared IPW and MI for addressing the missing data in the evaluation of time‐varying treatments, but they focused on missing confounders and monotone missing data patterns. This article assesses the relative advantages of MI and IPW to address missing data in both outcomes and confounders measured over time, and across monotone and non‐monotone missing data settings. Through a comprehensive simulation study, we find that MI consistently provided low bias and more precise estimates compared to IPW across a wide range of scenarios. We illustrate the implications of method choice in an evaluation of biologic drugs for patients with severe rheumatoid arthritis, using the US National Databank for Rheumatic Diseases, in which 25% of participants had missing health outcomes or time‐varying confounders.
Room‐Temperature Bulk Supramolecular Polymer Based on C3‐Symmetrical Benzene‐1,3,5‐tricarboxamides Having Two‐Armed Alkyl Groups as Side Chains
Authors: Ishigaki Yuzo , Yamanaka Motoshi , Hagio Takeshi , Ichino Ryoichi
Published: September 2023

To develop a bulk supramolecular polymer based on 1,3,5‐benzenetricarboxamide (BTA) without crystallinity at room temperature, C3‐synmetrical BTA derivatives with two‐armed alkyl groups were synthesized and characterized. IR and XRD measurements of the BTA derivatives suggested that the higher‐order structure obtained using these materials was hexagonal columnar, owing to the characteristic three‐fold hydrogen bonding. In DSC measurements, BTA having 10‐nonadecyl groups (10NDBTA) showed only a single transition point at 233 °C and maintained its mesophase down to −50 °C, whereas the other BTA derivatives showed a transition peak in the range of 20 to 131 °C and another in the range of 204 to 239 °C, corresponding to alkyl melting and dissociation of the stacked BTA cores, respectively. 13C‐SSNMR measurement of 10NDBTA indicated that not only the 10‐nonadecyl groups of the side chains but also the BTA cores forming the main chain of the supramolecular polymer show a unique high mobility even at ambient temperature.
Nanocatalyzed Synthesis of Benzoxazoles
Authors: Patel Shivnath R. , Patil Rajendra V. , Chavan Jagdish U. , Beldar Anil G.
Published: September 2023

Naturally, occurring as well as synthetic nitrogen and oxygen containing heterocyclic compounds like benzoxazoles and its derivatives have found to be playing a vital role in the Pharmaceutical, agriculture; polymer, material science and they also exhibits series of significant antimicrobial activities. In the last decade, an organic transformation has found abundant application of nanotechnology and nanoscience can aid design catalyst with excellent efficiency, selectivity and stability. Academics and industry have recently shown a lot of interest in the application of nanocatalysts, a field that is expanding significantly, to create sustainable and environmentally friendly processes for the synthesis of benzoxazole derivatives with multi‐component reactions (MCRs). Nanocatalyst reactions have advantages over conventional catalyst reactions because of the interaction of chemical reactants made possible by a high surface area ratio, simple purification, low catalyst loading, high atom economy, inexpensiveness, short reaction time, better yield, and recyclability of the nanocatalysts. In this review article, mainly focus is on the nanocatalysts fabrications, characterizations and their applications for the synthesis of benzoxazoles moiety during the last decennary (2011 to 2022).
Reaction Mechanism and Effect of Substituent in Direct Bromination of Indoles
Authors: Exlonk Gil A. , Hadad Cacier Z.
Published: September 2023

A reaction mechanism for the direct bromination of substituted indoles in dimethylformamide solution at 298.15 K and 1 atm is proposed and studied. It consists of two steps, the first one, in which the lowest unoccupied molecular orbital of Br2 overlaps with the highest occupied molecular orbital of the substituted indole, is the rate‐determining step. A linear correlation is observed between the electron‐withdrawing power of the substituent (expressed through the relative molecular electrostatic potential) and the Gibbs free energy barrier of the reaction‘s rate‐determining step,
. This correlation is suggested for estimating
in other unexplored cases. The variation of
with a change in substituents is primarily governed by electronic factors, but the presence of
itself is due to entropic factors. The rate of the bromination reaction under the studied conditions diminishes with a change in the substituent, R, following the order: R=−OCH3, −CH3, −H, −CCH3CH2, −C6H5, −CH2OH, −F, −SCH2CH3, −Cl, −Br, −COCH3, −COOH, −NC, −COH, and −CN.
Flavothione‐3‐carboxylate Derivatives: Synthesis, Molecular Docking, and Antiproliferative Activity against Breast Cancer
Authors: Solanki Naishadh , Desai Sweta , Dedania Ronak
Published: September 2023

This study explores the potential of Flavothione‐3‐Carboxylate derivatives as inhibitors of glycogen synthase kinase 3 beta (GSK‐3β) for the treatment of breast cancer. GSK‐3β plays a critical role in cancer cell survival, proliferation, and chemotherapy resistance. Inhibitors of GSK‐3β have emerged as promising candidates for developing new cancer therapies. Flavatione‐3‐carboxylate derivatives were synthesized in a single step through a three‐component reaction using 4‐hydroxycoumarin, 2‐nitrovinylbenzene, and alcohol, catalyzed by 4‐dimethylaminopyridine. The reaction was followed by treatment with Lawson's reagent in toluene solvent. The structures of these derivatives were elucidated by infrared (IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS). Their drug‐likeness was assessed using the SwissADME tool. The antiproliferative activity of the synthesized compound was evaluated on estrogen‐dependent MCF‐7 and non‐estrogen‐dependent MDA‐MB‐231 breast cancer cell lines. Among the tested compounds, NS16 demonstrated significant antiproliferative activity with an IC50 value of 5.69±1 μM against MCF‐7 ER+ cells, while NS04, NS05, NS07, and NS08 showed efficacy against MDA‐MB‐231 ER‐ cells with IC50 values ranging from 4.56±1 to 7.07±1 μM. Furthermore, the GSK‐3β activity assay revealed potent inhibitory effects of nitrophenyl and halo‐phenyl Flavothiones‐3‐Carboxylate derivatives on GSK‐3β activity. However, compounds NS15 and NS16 exhibited lower efficacy in inhibiting the enzyme, despite their anticancer activity.
Self‐Assembly of Water‐Soluble Glycoluril Molecular Clips Driven by Naphthalene‐Naphthalene Interaction
Authors: Xue Weijian , Li Huiqian , Ling Xiangyu , Zhang Ying , Liu Yang , Zhao Bing , Yin Yanbing , Guo Xiangfeng
Published: September 2023

A water‐soluble C‐shaped receptors based on glycoluril and naphthalene building blocks is reported. The complexation formed in water was confirmed by 1H NMR spectroscopy and NOESY technique and DOSY technique. 1H NMR spectroscopy, fluorescence spectroscopy and DLS measurements provide strong evidence that compound 2 undergoes self‐recognition that naphthalene moiety can bind into the bisnaphthalene cleft and head‐to‐tail host–guest complexation to form new supramolecular assemblies in water. SEM and AFM visualized that the complexation formed the cyclic structure. This kind of highly designable monomer structure has great possibility to construct novel supramolecular polymer materials.