bluuebunny/crossref_metadata_2025 huggingface dataset:
Kinetic Studies and Temperature‐Induced Morphological Changes of Peptide Decorated Nano‐Objects via Polymerization‐Induced Self‐Assembly
Authors: Benkhaled Belkacem Tarek , Chouirfa Hamza , Vezenkov Lubomir , Gomri Chaimaa , Chaix Arnaud , Subra Gilles , Ladmiral Vincent , Semsarilar Mona
Published: August 2023

In the present work, combining polymerization‐induced self‐assembly (PISA) with self‐assembling peptides (SAPs) peptide−polymer hybrid nanostructures are prepared, harnessing the advantages of PISA and the self‐assembling driving force of SAPs. A tripeptide methacrylamide denoted as MAm‐GFF, where MAm, G, and F stand for methacrylamide, glycine, and phenylalanine, is copolymerized with glycerol monomethacrylate (GMA) by reversible addition−fragmentation chain transfer polymerization (RAFT) in dimethylformamide to produce a P(GMA62‐stat‐(MAm‐GFF)7) macromolecular chain transfer agent (macro‐CTA). This peptide‐containing macro‐CTA is then successfully chain‐extended with poly(2‐hydroxypropyl methacrylate) (PHPMA) by aqueous dispersion PISA, forming P(GMA62‐stat‐(MAm‐GFF)7)‐b‐PHPMA27 self‐assembled objects. The impacts of temperature and monomer conversion on the morphologies formed during the PISA process are investigated by analyzing samples withdrawn at different time during the polymerization of HPMA using transmission electron microscopy (TEM) and dynamic light scattering (DLS) at different temperatures (5–70 °C).
Ultrasonic in situ evaluation of the bolt preload without referencing an unloaded state using a combination of longitudinal and transverse waves
Authors: Niwinski T. J. , Kraemer F. , Klein M. , Oechsner M. , Herter S. , Becker M. M.
Published: August 2023

Die ultraschallbasierte Vorspannkraftermittlung an Schrauben wird derzeit überwiegend mit der Ein‐Moden‐Methode realisiert. Diese Methode basiert auf der Laufzeitmessung von Longitudinalwellen. Hierbei ist für jede Schraube eine Referenzmessung im nicht verspannten Zustand notwendig. In der vorliegenden Publikation wird die Ein‐Moden‐Methode um eine weitere Ultraschallwellenart, die Transversalwelle, ergänzt. Es wird dargestellt, dass mit der Zwei‐Moden‐Methode auf eine Referenzmessung im nicht verspannten Zustand verzichtet werden kann. Ein analytisches Verfahren zur Bestimmung des schraubfallspezifischen akusto‐elastischen Materialkennwerts (K‐Wert) wird vorgestellt, welcher für die ultraschallbasierte Vorspannkraftermittlung notwendig ist. Die analytisch ermittelten K‐Werte werden mit experimentellen K‐Werten aus Zugversuchen an Schrauben verglichen. Der Einfluss von Werkstoff, Festigkeitsklasse und Oberflächenschutzsystem wurde an zylindrischen Werkstoffproben ermittelt. In Bauteilversuchen wurden Vorspannkräfte an montierten Schrauben mit der Zwei‐Moden‐Methode ermittelt, ein möglicher Einfluss des Montageverfahrens untersucht und die Ergebnisse hinsichtlich ihrer Genauigkeit interpretiert.
Monocytes in neonatal stroke and hypoxic‐ischemic encephalopathy: Pathophysiological mechanisms and therapeutic possibilities
Authors: Pimentel‐Coelho Pedro M.
Published: August 2023

Neonatal arterial ischemic stroke (NAIS) and neonatal hypoxic‐ischemic encephalopathy (HIE) are common causes of neurological impairments in infants, for which treatment options are very limited. NAIS and HIE induce an innate immune response that involves the recruitment of peripheral immune cells, including monocytes, into the brain. Monocytes and monocyte‐derived cells have the potential to contribute to both harmful and beneficial pathophysiological processes, such as neuroinflammation and brain repair, but their roles in NAIS and HIE remain poorly understood. Furthermore, recent evidence indicates that monocyte‐derived macrophages can persist in the brain for several months following NAIS and HIE in mice, with possible long‐lasting consequences that are still unknown. This review provides a comprehensive overview of the mechanisms of monocyte infiltration and their potential functions in the ischemic brain, focusing on HIE and NAIS. Therapeutic strategies targeting monocytes and the possibility of using monocytes for cell‐based therapies are also discussed.
Impact of correlated observation errors on the conditioning of variational data assimilation problems
Authors: Goux Olivier , Gürol Selime , Weaver Anthony T. , Diouane Youssef , Guillet Oliver
Published: August 2023

An important class of nonlinear weighted least‐squares problems arises from the assimilation of observations in atmospheric and ocean models. In variational data assimilation, inverse error covariance matrices define the weighting matrices of the least‐squares problem. For observation errors, a diagonal matrix (i.e., uncorrelated errors) is often assumed for simplicity even when observation errors are suspected to be correlated. While accounting for observation‐error correlations should improve the quality of the solution, it also affects the convergence rate of the minimization algorithms used to iterate to the solution. If the minimization process is stopped before reaching full convergence, which is usually the case in operational applications, the solution may be degraded even if the observation‐error correlations are correctly accounted for. In this article, we explore the influence of the observation‐error correlation matrix () on the convergence rate of a preconditioned conjugate gradient (PCG) algorithm applied to a one‐dimensional variational data assimilation (1D‐Var) problem. We design the idealized 1D‐Var system to include two key features used in more complex systems: we use the background error covariance matrix () as a preconditioner (B‐PCG); and we use a diffusion operator to model spatial correlations in and . Analytical and numerical results with the 1D‐Var system show a strong sensitivity of the convergence rate of B‐PCG to the parameters of the diffusion‐based correlation models. Depending on the parameter choices, correlated observation errors can either speed up or slow down the convergence. In practice, a compromise may be required in the parameter specifications of and between staying close to the best available estimates on the one hand and ensuring an adequate convergence rate of the minimization algorithm on the other.
A coordinate transformation based barycentric interpolation collocation method and its application in bending, free vibration and buckling analysis of irregular Kirchhoff plates
Authors: Huang Z. M. , Peng L. X.
Published: August 2023

In this article, a meshless barycentric interpolation collocation method (BICM) with coordinate transformation is proposed to solve the governing partial differential equations (PDEs) for bending, free vibration and buckling problems of irregular plates. First, the coordinate transformation equations for first to fourth derivatives are introduced. Then the PDEs and boundary conditions defined in a physical domain are transformed into a rectangular domain (reference domain) with the derived differential interpolation matrices. The presented BICM can solve the PDEs based on the reference domain and is adaptive to irregular problem domains. Finally, the bending, free vibration and buckling problems of Kirchhoff plates with irregular shapes are studied with the proposed method. To illustrate the effectiveness of the proposed method, the results are compared with those given by theoretical solutions, finite element methods and literature.
Preventive effect of aripiprazole once monthly on rehospitalization for bipolar disorder: A multicenter 1‐year retrospective mirror image study
Authors: Goto Junichi , Shono Masahiro , Abe Yasuhisa , Fujita Yasutaka , Ueda Keishi , Yoshida Binchi , Nabeshima Yoshihiro
Published: August 2023

Aim

We conducted a 1‐year retrospective mirror‐image study to investigate the effect of aripiprazole once monthly (AOM) on rehospitalization for bipolar disorder.

Methods

Participants were recruited from psychiatric emergency and acute care hospitals in western Japan. We included 39 participants with bipolar disorder who had been administered AOM for at least 1 year with no missing medical records during the observational period. The primary outcomes were rehospitalization rate, number of rehospitalizations, total hospitalization days, and time to rehospitalization in the context of overall psychiatric readmissions. The significance level was set at p < 0.05.

Results

AOM significantly reduced the rehospitalization rate from 23/39 (59%) to 7/39 (18%) (p = 0.001). The number of rehospitalizations decreased significantly from a mean of 0.85 per person‐year to 0.41 per person‐year (p = 0.048). The total hospitalization days significantly decreased from a mean of 34.9 days to 14.4 days (p = 0.008). AOM significantly prolonged the time to rehospitalization (p < 0.001).

Conclusion

This study found that AOM reduces overall psychiatric rehospitalization for bipolar disorder based on data from 1 year before and after AOM administration in the real‐world setting. Future studies should examine the robustness and persistence of the rehospitalization preventive effect of AOM with larger sample sizes and longer observation periods beyond 1 year.
Numerical Fréchet derivatives of the displacement tensor for 2.5‐D frequency‐domain seismic full‐waveform inversion in viscoelastic TTI media
Authors: Yang Qingjie , Zhou Bing , Engsig Marcus , Won Moosoo , Riahi Mohamed Kamel , Al‐khaleel Mohammad , Greenhalgh Stewart
Published: August 2023

Derivatives of the displacement tensor with respect to the independent model parameters of the subsurface, also called Fréchet derivatives (or sensitivity kernels), are a key ingredient for seismic full‐waveform inversion (FWI) with a local‐search optimization algorithm. They provide a quantitative measure of the expected changes in the seismograms due to perturbations of the subsurface model parameters for a given survey geometry. Because 2.5‐D wavefield modelling involves a real point source in a 2‐D geological model with 3‐D (spherical) wave properties, it yields synthetic data much closer to the actual practical field data than the commonly used 2‐D wave simulation does, which uses an unrealistic line‐source in which the waves spread cylindrically. Based on our recently developed general 2.5‐D wavefield modelling scheme, we apply the perturbation method to obtain explicit analytic expressions for the derivatives of the displacement tensor for 2.5‐D/2‐D frequency‐domain seismic FWI in general viscoelastic anisotropic media. We then demonstrate the numerical calculations of all these derivatives in two common cases: (1) viscoelastic isotropic; and (2) viscoelastic tilted transversely isotropic (TTI) solids. Examples of the differing sensitivity patterns for the various derivatives are investigated and compared for four different homogeneous models involving 2‐D and 2.5‐D modelling. Moreover, the numerical results are verified against the analytic solutions for homogeneous models. We further validate the numerical derivatives in a 2‐D heterogeneous viscoelastic TTI case by conducting a synthetic data experiment of frequency‐domain FWI to individually recover the 12 independent model parameters (density, dip angle, 5 elastic moduli and 5 corresponding Q‐factors) in a simple model comprising an anomalous square box target embedded in a uniform background. Another 2.5‐D multi‐target model experiment presenting impacts from four common seismic surveying geometries validates the Fréchet derivatives again.
Impact of visceral fat on coronary artery disease as defined by quantitative computed tomography angiography
Authors: Karlsberg Daniel , Steyer Henry , Fisher Rebecca , Crabtree Tami , Min James K. , Earls James P. , Rumberger John
Published: August 2023

Objective

Obesity is associated with all‐cause mortality and cardiovascular disease (CVD). Visceral fat (VF) is an important CVD risk metric given its independent correlation with myocardial infarction and stroke. This study aims to clarify the relationship between the presence and severity of VF with the presence and severity of coronary artery plaque.

Methods

In 145 consecutive asymptomatic patients, atherosclerosis imaging‐quantitative computed tomography was performed for total plaque volume (TPV) and percentage atheroma volume, as well as the volume of noncalcified plaque (NCP), calcified plaque, and low‐density NCP (LD‐NCP), diameter stenosis, and vascular remodeling. This study also included VF analysis and subcutaneous fat analysis, recording of outer waist circumference, and percentage body fat analysis.

Results

The mean age of the patients was 56.1 [SD 8.5] years, and 84.0% were male. Measures of visceral adiposity (mean [SD, Q1–Q3 thresholds]) included estimated body fat, 28.7% (9.0%, 24.1%–33.0%); VF, 169.8 cm2 (92.3, 102.0–219.0 cm2); and subcutaneous fat, 223.6 mm2 (114.2, 142.5–288.0 mm2). The Spearman correlation coefficients of VF and plaque volume included TPV 0.22 (p = 0.0074), calcified plaque 0.12 (p = 0.62), NCP 0.25 (p = 0.0023), and LD‐NCP 0.37 (p < 0.0001). There was a progression of the median coronary plaque volume for each quartile of VF including TPV (Q1: 19.8, Q2: 48.1, Q3: 86.4, and Q4: 136.6 mm3 [p = 0.0098]), NCP (Q1: 15.7, Q2: 35.4, Q3: 86.4, and Q4: 136.6 mm3 [p = 0.0032]), and LD‐NCP (Q1: 0.6, Q2: 0.81, Q3: 2.0, and Q4: 5.0 mm3 [p < 0.0001]).

Conclusions

These findings demonstrate progression with regard to VF and TPV, NCP volume, and LD‐NCP volume. Notably, there was a progression of VF and amount of LD‐NCP, which is known to be high risk for future cardiovascular events. A consistent progression may indicate the future utility of VF in CVD risk stratification.
Stochastic maximum principle for discrete time mean‐field optimal control problems
Authors: Ahmadova Arzu , Mahmudov Nazim I.
Published: August 2023

This article studies optimal control of a discrete‐time stochastic differential equation of mean‐field type with coefficients dependent on function of the law and state of the process. A new version of the maximum principle for discrete‐time mean‐field type stochastic optimal control problems is established, using new discrete‐time mean‐field backward stochastic equations. The cost functional is also of mean‐field type. The study derives necessary first‐order and sufficient optimality conditions using adjoint equations that take the form of discrete‐time backward stochastic differential equations with a mean‐field component. An optimization problem for production and consumption choice is used as an example.
Density functional theory investigation of the energy storage potential ofgraphene‐polypyrrolenanocomposites as high‐performance electrode for Zn‐ion batteries
Authors: Adedoja Oluwaseye Samson , Sadiku Emmanuel Rotimi , Hamam Yskandar
Published: August 2023

The present research explores, through the density functional theory (DFT) calculations, the viability of graphene‐polypyrrole (G/PPy) nanocomposites as an effective material for energy storage in Zn‐ion batteries. To this end, the CASTEP calculator in the Materials Studio software was employed to examine the electronic and structural properties of the nanocomposites and their potential to enhance energy storage capabilities of Zn‐ion batteries. Specifically, the study investigates the interaction of the Zn‐adatom with the nanocomposites, electronic properties, specific capacity, Zn adatom diffusion behavior, structural, and thermal stability, as well as the mechanisms through which the nanocomposites store energy. The results show that the adsorption calculation for PPy onto the graphene nanosheet has an exothermic adsorption energy of −1.68 eV and an adsorption height of 3.28 Å. The loading of Zn atoms onto the Gr/PPy nanocomposite yielded a maximum specific capacity of 510.12 mAh g−1, resulting into a weak adsorption energy of −0.078 eV. The nanocomposite exhibited an extremely low Zn diffusion barrier of 12 meV, enabling a fast Zn diffusion on its surface. These findings suggest that G/PPy nanocomposites hold promise as a material to enhance energy storage in Zn‐ion batteries. The study, through DFT calculations, offers valuable insights into the electronic and structural properties of G/PPy nanocomposites and their potentials for improved energy storage in Zn‐ion batteries. It thus, contributes significantly to the current understanding of energy storage materials and provides a foundation for further research on the development of more effective and efficient energy storage solutions.

Highlights

DFT investigations of G/PPy nanocomposites show potential for improved energy storage in Zn‐ions batteries.

The electronic and structural properties of the nanocomposites offer valuable insight into their feasibility.

The results show that G/PPy nanocomposites can enhance energy storage in Zn‐ion batteries.

It contributes to the current understanding of energy storage nanocomposite materials.

It provides a framework for developing effective and efficient energy storage technologies.
Outcomes of psychological support skills training for cancer care staff: Skill acquisition, work engagement, mental wellbeing and burnout
Authors: Malins Sam , Boutry Clement , Moghaddam Nima , Rathbone James , Gibbons Felicity , Mays Chloe , Brooks Daniel , Levene Joanna
Published: August 2023

Objective

Psychological support skills training has the potential to improve both the ability of cancer staff to help their patients, and staff wellbeing. However, few recent studies have assessed both these outcomes or incorporated current developments in psychological skills training, such as deliberate practice, which includes the use of iterative, corrective feedback to identify and improve individualised skill deficits. No studies have evaluated the contribution that psychological skills training could make to cancer care staff wellbeing and expertise in the wake of the COVID‐19 pandemic. This study aimed to evaluate staff skill acquisition and work‐related wellbeing following psychological support skills training that applied deliberate practice principles.

Method

A 2‐day training and monthly supervision was offered to 145 cancer care staff that focused on brief assessment and intervention skills for patients experiencing mental health problems after cancer diagnosis and treatment. Deliberate practice principles were used to focus training on skills practice and feedback, over technique description. Self‐reported ability to perform key skills taught, staff mental wellbeing, work engagement, and burnout were assessed at baseline, 3‐month and 8‐month follow‐up.

Results

Significant improvements in skills, mental wellbeing, burnout and work engagement were reported at 8‐month follow‐up. Full engagement in both training sessions was predicted by poorer baseline mental wellbeing, more positive evaluation of initial training, supervision attendance, and shorter follow‐up.

Conclusion

A 2‐day psychological support skills training using deliberate practice principles may support improvement in staff skill, mental wellbeing, burnout and work engagement.
Variants in FGF10 cause early onset of severe childhood interstitial lung disease: A detailed description of four affected children
Authors: Schütz Katharina , Schmidt Axel , Schwerk Nicolaus , Renz Diane Miriam , Gerard Benedicte , Schaefer Elise , Antal Maria Cristina , Peters Sophia , Griese Matthias , Rapp Christina K. , Engels Hartmut , Cremer Kirsten , Bergmann Anke Katharina , Schmidt Gunnar , Auber Bernd , Kamp Jan C. , Laenger Florian , von Hardenberg Sandra
Published: August 2023

Introduction

Fibroblast growth factor 10 (FGF10) is a signaling molecule with a well‐established role for lung branching morphogenesis. Rare heterozygous, deleterious variants in the FGF10 gene are known causes of the lacrimo‐auriculo‐dento‐digital (LADD) syndrome and aplasia of lacrimal and salivary glands. Previous studies indicate that pathogenic variants in FGF10 can cause childhood Interstitial Lung Disease (chILD) due to severe diffuse developmental disorders of the lung, but detailed reports on clinical presentation and follow‐up of affected children are lacking.

Methods

We describe four children with postnatal onset of chILD and heterozygous variants in FGF10, each detected by exome or whole genome sequencing.

Results

All children presented with postnatal respiratory failure. Two children died within the first 2 days of life, one patient died at age of 12 years due to right heart failure related to severe pulmonary hypertension (PH) and one patient is alive at age of 6 years, but still symptomatic. Histopathological analysis of lung biopsies from the two children with early postpartum demise revealed diffuse developmental disorder representing acinar dysplasia and interstitial fibrosis. Sequential biopsies of the child with survival until the age of 12 years revealed alveolar simplification and progressive interstitial fibrosis.

Discussion

Our report extends the phenotype of FGF10‐related disorders to early onset chILD with progressive interstitial lung fibrosis and PH. Therefore, FGF10‐related disorder should be considered even without previously described syndromic stigmata in children with postnatal respiratory distress, not only when leading to death in the neonatal period but also in case of persistent respiratory complaints and PH.
Evolution of the main channel of the Yangtze River
Authors: Lu Jinyou , Zhu Yonghui , Jin Zhongwu , Guo Xiaohu , Guo Chao , Chen Peng , Wang Yanjun , Hu Chengwei , Yuan Yuan
Published: August 2023

The construction and operation of the Three Gorges Reservoir and the cascade reservoirs upstream have significantly altered the processes of flow and sediment in the main and tributary channels of the Yangtze River. This has led to substantial adjustments in the riverbed through erosion and deposition, thereby impacting flood protection, water resource utilization, navigation, and the aquatic environment in the Yangtze River basin. In this study, prototype measurements were used to analyze the variations in runoff and sediment load in the main channel of the Yangtze River, as well as the changes and evolution of the riverbed. Mathematical modeling was done to predict the trends in reservoir sedimentation and riverbed adjustments. The results indicate that, apart from the significantly increased runoff and sediment load in the river source region (Zhimenda station) over the past two decades, there is no clear unidirectional trend of increasing or decreasing in the main and tributary annual runoff of the Yangtze River. However, the release of reservoir outflows undergoes significant changes throughout the year due to reservoir regulation. Suspended sediment load in the upper Yangtze River has been decreasing since the 1990s, especially after the operation of the Three Gorges Reservoir and the four cascade reservoirs in the lower reach of the Jinsha River. The factors influencing flow and sediment variations include mainly climate change and human activities such as reservoir operation and soil and water conservation. The significant changes in flow and sediment conditions have disrupted the original relative equilibrium state of the main channel of the Yangtze River, leading to riverbed adjustments. The river sections in the upper reach, located within reservoir areas, have shifted from erosional state under natural conditions to accumulative state, while the middle and lower reaches have transitioned from a relatively equilibrium state to a process dominated by erosion and reconstruction. Overall, the river regime in the reservoir area and downstream of the Three Gorges Dam remains relatively stable, but there have been adjustments in some local river sections, for example, in the curved sections, particularly in the sharply curved sections downstream of the Three Gorges Dam, where gradual or abrupt chute cutoff has occurred. In the foreseeable future, the river channel downstream of the Three Gorges Dam will remain in an unsaturated state regarding sediment transport. The process of river channel erosion will persist for a long time and have far‐reaching consequences. Some long straight sections, multiple bifurcation sections, and sections with large curvature are expected to undergo certain adjustments in the river regime, necessitating continuous observation, long‐term monitoring, and timely river management and channel governance.
Forecasting emergency department waiting time using a state space representation
Authors: Trinh Kelly , Staib Andrew , Pak Anton
Published: August 2023

The provision of waiting time information in emergency departments (ED) has become an increasingly popular practice due to its positive impact on patient experience and ED demand management. However, little scientific attention has been given to the quality and quantity of waiting time information presented to patients. To improve both aspects, we propose a set of state space models with flexible error structures to forecast ED waiting time for low acuity patients. Our approach utilizes a Bayesian framework to generate uncertainties associated with the forecasts. We find that the state‐space models with flexible error structures significantly improve forecast accuracy of ED waiting time compared to the benchmark, which is the rolling average model. Specifically, incorporating time‐varying and correlated error terms reduces the root mean squared errors of the benchmark by 10%. Furthermore, treating zero‐recorded waiting times as unobserved values improves forecast performance. Our proposed model has the ability to provide patient‐centric waiting time information. By offering more accurate and informative waiting time information, our model can help patients make better informed decisions and ultimately enhance their ED experience.
Preparation of Fe3O4 Magnetic Material Modified by Fulvic Acid and Its Adsorption Performance for Methylene Blue
Authors: Wu Zeqing , Fan Hongxian , Hu Xiaoxue , Zhang Songmei , Wen Yeqian , Li Gang
Published: August 2023

In this paper, a kind of Fe3O4 magnetic nano material modified by fulvic acid (FA) was prepared and used for removing methylene blue in wastewater. The structure and morphology of the material were characterized by FT‐IR, PXRD, BET, XPS, VSM, SEM and TEM. The results showed that FA successfully coated on the surface of Fe3O4 magnetic nano particles. The newly prepared magnetic material had large specific surface area and porous structure. The specific surface area of the material was 92.15 m2/g. The average pore size of the material was 8.917 nm. Its saturation magnetization could reach to 55.74 emu/g. The magnetic responsiveness of the material was obvious. The magnetic material could be recovered by the magnet so it was easy to separate with the solution. The adsorption kinetic data fitted better with pseudo second order kinetic equation. The isothermal adsorption processes of the modified material to methylene blue had better linear correlation with Langmuir isothermal adsorption model. The thermodynamic parameter results indicated that the adsorption processes of the material to methylene blue were spontaneous exothermic processes. The results of the cyclic experiments indicated that the material had a certain value for reuse.
A Theoretical Molecular Design of Acridine/Anthracene‐Polyoxometalate Hybrid Materials for Enhanced Dye‐Sensitized Solar Cells Performance
Authors: Al‐Khafaji Mariam K. , Al‐Yasari Ahmed , Mohammed Adnan I.
Published: August 2023

Four novel organoimido‐substituted hexamolybdate dyes featuring acridine/anthracene donors for dye‐sensitized solar cells (DSSCs) have been designed and studied using a combination of density functional theory (DFT) and time‐dependent density functional theory (TDDFT) calculations. The energy levels of frontier molecular orbitals, absorption spectra with electronic transition characters, and photovoltaic parameters of dyes 1–4 were systematically evaluated. The results confirm the suitability of all the studied dyes for n‐type DSSCs. The investigated dyes could be introduced as an active co‐absorbent as well as main dye. All dyes showed remarkable reorganization energy for electron transport (λe) and hence increased electron transfer rate. Due to the strong absorption in the visible region, as well as high light harvesting efficiency (LHE), dye regeneration efficiency (DRE), and electron injection efficiency (Φinj), dyes 2 and 3 are the most promising candidates for high performance DSSC materials.
A Combined Ultrasound–Microwave Assisted Alcoholic–Alkaline Method for Preparation of Granulated Cold‐Water‐Soluble Starch
Authors: Liu Yao , Zhu Lvzhou , Yu Xi , Xu Yuqing , Zhong Tian
Published: August 2023

In order to further improve the solubility of granulated cold‐water‐soluble starch (GCWSS), this study develops a new, combined ultrasound–microwave assisted method based on the traditional alcoholic–alkaline method. Following a single‐factor experiment, an orthogonal experiment is conducted to determine optimized parameters and proportions. Three typical samples with relatively low, medium, and high solubility, respectively, are selected for characterization, including with scanning electron microscopy (SEM), polarization characteristics, Brabender viscosity, Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The results show that the combined ultrasound–microwave treatment significantly improves the solubility of modified starch, achieving a highest sample solubility of 92.45%.
Flow Simulation of a New Horizontal Axis Wind Turbine with Multiple Blades for Low Wind Speed
Authors: Abo-Serie Essam , Oran Elif
Published: August 2023

In this paper, a new design of a small horizontal-axis wind turbine is introduced. The design is based on the authors’ patent, which uses permanent magnets impeded into a shroud that holds the rotor blades. The generator coils are installed on a fixed diffuser that houses the rotor and acts as a wind concentrator. Therefore, the new design has no hub and is based on direct coupling for electricity generation. The main features of the design have been explored to highlight the advantages with a focus on how the new design can be integrated with the recent development of green buildings. The effect of increasing the number of blades and blade chord distribution on turbine performance has been investigated for the new turbine. Initial design and analysis were carried out using the Blade Element Momentum method and CFD simulations to identify the turbine performance and examine the flow characteristics. The results showed that further energy can be extracted from the turbine if the blade chord size increases at the shroud location and reduces at the turbine hub for a low Tip Speed Ratio TSR within the range of 1.5–3. Furthermore, having more blades can significantly increase the power coefficient and extend the range of operation with a high power coefficient. The number of blades, however, has to be optimised to achieve maximum power relative to the cost. Adding a diffuser and flanges surrounding the turbine can further increase the energy extracted from the wind at low speed.
Assessment of Effectiveness of Hollow Fins for Performance Enhancement of Solar Still Device Using Simulation Approach
Authors: Ullah Hafiz Khadim , Ismail Sikiru Oluwarotimi , Prasad Kumar Shantanu
Published: August 2023

Unavailability of relatively clean water for several industrial, domestic and agricultural purposes is a serious concern to many regions of the world today. This challenge is growing worse with the increasing world global warming and human population. Therefore, there is need to research into an innovative, sustainable and/or improved technology for an efficient and effective solution, such as desalination. Desalination of freely available sea water is considered a promising source of fresh water. Solar radiation is abundant and can be used to desalinate water, using a solar still device. Also, it is important to increase the productivity of the solar still device through hollow fin modification. Therefore, the effectiveness of this improvement was investigated in this study, using an analysis system (ANSYS) Fluent computational fluid dynamic (CFD) simulation. Appropriate models were used to describe the physical processes, including condensation, evaporation, multiphase flow, surface tension and solar radiation. A close agreement between the simulation values of solar energy and the water temperature in the basin was observed when compared with the experimental data from the literature. Velocity of 0.259 m/s, pressure of 55.8 Pa, temperature of 57.85 ºC and mass transfer rate of 1.41 kg/m3/s were obtained in the mid-plane of the improved double slope single basin (DSSB). The degree of improvement was 5–7% when compared with the existing models. Importantly, this process is economically efficient and can support the concepts of sustainability and healthy living, especially in rural areas.
Development of a CFD Model for the Estimation of Windage Losses Inside the Narrow Air Gap of an Enclosed High-Speed Flywheel
Authors: Eltaweel Mahmoud , Kalyvas Christos , Chen Yong , Herfatmanesh Mohammad Reza
Published: August 2023

Concerns over global warming and the need to reduce carbon emissions have prompted the development of novel energy recovery systems. During urban driving, a significant amount of energy is lost due to continuous braking, which can be recovered and stored. The flywheel energy storage system can efficiently recover and store the vehicle's kinetic energy during deceleration. In this study, a Computational Fluid Dynamics (CFD) model was developed to assess the impact of air gap size, and rotor cavity pressure environment on the aerodynamic performance of an enclosed non-ventilated flywheel energy recovery system. Consequently, the flywheel rotor skin friction coefficients for various air gap sizes have been numerically determined to predict the windage losses over a wide operating range. The presented study aims to identify a correlation that accurately fits the rotor skin friction coefficients for a range of air gap sizes and operating conditions. Model validation was carried out to assess the validity of the CFD results, which showed good agreement between numerical and experimental data. The results demonstrated that the increase in the air gap size can lead to up to a 19% reduction in the windage loss depending on the operating speed of the flywheel, while the windage loss can be reduced by 33% when the operating pressure is reduced to 500 mbar. Windage losses can be reduced by 45% when the airgap size is greatest, and the operating pressure is lowest.
The Impact of Strategic Environmental Management Capabilities on the Competitiveness of an Oil and Gas Industry’s Supply Chain: An Empirical Evaluation of the Natural Resource-Based View of Firms
Authors: Olajide Olatunde , Kamal Muhammad Mustafa , Kwak Dong-Wook , He Qile , Lim Ming
Published: August 2023

The Oil and Gas (O&G) industry has been subjected to stringent environmental regulations and increasing stakeholders’ criticisms because of its devastating negative environmental impacts. Consequently, firms operating in the industry’s supply chain are increasingly facing intense pressures to develop the strategic capabilities for implementing green practices to reduce the environmental impacts of operations. From a theoretical perspective, the Natural Resource-Based View (NRBV) suggests that the strategic environmental capabilities of pollution prevention (PPC), product stewardship (PSC) and clean technology (CTC) can generate sustained competitive advantage for firms. However, the extant empirical research investigating the impact of the three NRBV strategic environmental capabilities (PPC, PWC and CTC) on firms’ competitive performance has yielded inconsistent results. Therefore, this paper adopts the theoretical lens of NRBV to develop and empirically assess an integrated framework of strategic environmental management capabilities (SEMC) and competitiveness in the context of the Nigerian O&G industry. Using a multiple regression technique to analyse the responses of 214 managers across the supply chain of the Nigerian O&G industry, this study examines the impact of the three NRBV-based SEMC (PPC, PWC and CTC) on the economic and environmental competitiveness of the firms operating in the supply chain of the Nigerian O&G industry. First, the results indicate that the three SEMCs have positive impacts on the environmental competitiveness of the O&G firms. However, while PPC and PSC are positively related to the economic competitiveness of firms, CTC has no statistically significant impact on economic competitiveness. These findings suggest that O&G firms in developing nations need to channel efforts to build their SEMCs for implementing green practices to enhance their economic and environmental competitiveness. The results further highlight the need for policymakers in petroleum-producing nations to promote policies that foster the adoption of green practices by O&G firms.
Multi-objective Optimisation of a Wastewater Anaerobic Digestion System
Authors: Ashraf R. J. , Nixon Jonathan D. , Brusey J.
Published: August 2023

This paper looks at multi-objective optimisation of a wastewater AD system where the model is demonstrated for a case study plant. Anaerobic Digestion Model No. 1 (ADM1) was used to predict biogas yields from the digester. Interviews, with plant owners, and plant data were used to identify the objective functions and decision variables. The decision variables were defined to be the substrate feeding rate for each of the digesters and the ratio of biogas sent between a combined heat and power (CHP) plant and a biogas upgrading unit (BUU). The objectives set were to maximise the overall substrate feeding rate through the AD plant, maximise the overall energy output and minimise the running cost of the plant. Results from the optimisation study showed that the amount of sludge processed through the AD plant increased by 17.7% and the running cost of the plant reduced by 6.2%. These results demonstrate how performance of AD plants can be significantly improved by multi-objective optimisation techniques.
Performance of Different Optimization Solvers for Designing Solar Linear Fresnel Reflector Power Generation Systems
Authors: Sirimanna M. P. G. , Nixon Jonathan D. , Innocente M. S.
Published: August 2023

Linear Fresnel Reflector (LFR) is an emerging solar thermal power generation technology that benefits from a simple and low-cost construction in comparison to more conventional Concentrating Solar thermal Power (CSP) generation technologies such as parabolic trough and power tower. Although LFR technology presents the drawbacks of lower energy conversion efficiency and higher energy cost, these can be offset by optimizing its design. This has not been sufficiently addressed due to the complex interactions between solar rays, heat transfer modes, and design variables. This work presents a systematic approach to select suitable optimization methods for the design of LFR systems. Thus, a mathematical model is developed to carry out simultaneous raytracing and thermal simulations aiming to provide an estimation of the system’s total conversion efficiency to be maximized. In order to compare the performance at solving this problem of a range of optimization algorithms with different characteristics, three derivative-based, two derivative-free, one population-based, and the simulated annealing methods are used in the numerical experiments. Only one design variable and a simple LFR system with a trapezoidal receiver are considered in the first instance. Only those algorithms which are successful at solving this simple problem are then tested on the optimal design with multiple variables. An exhaustive search is also conducted to check accuracy. Results show that pattern search, simulated annealing, and genetic algorithms perform best at solving the simulation-based LFR optimal design problem.
Pre-existing Mathematics Teacher Characteristics
Authors: Chapman Olive
Published: August 2023

This chapter addresses the pre-existing mathematics teacher characteristics (PMTC) of prospective mathematics teachers on entry to their teacher education program. Pre-existing teacher characteristics include abilities, knowledge, and attitudes that a candidate for admission to a teacher preparation program possesses on entry, as well as a candidate’s aptitude for teaching. The chapter provides an overview of a survey of mathematics education research for the period 2000 to 2020 with a focus on the three categories of the types and nature of pre-existing teacher characteristics the studies addressed. These categories emerging from the survey are pre-existing mathematical content knowledge and skills, pre-existing mathematics-related pedagogical knowledge and ability, and pre-existing mathematics-related beliefs. The studies are also discussed from the perspective of the evolution of the research on PMTC and implications regarding future evolution of research on PMTC.
The Research on Mathematics Teaching and Planning: Theoretical Perspectives and Implications of Teachers’ Pre-post Classroom Activities
Authors: Manizade Agida G. , Moore Alexander S. , Beswick Kim
Published: August 2023

Lesson planning, assessment, and reflection constitute the key actions that teachers perform when students are not present in the classroom (henceforth, “Type D” variable). These “pre- and post-”actions are the most direct ways through which teachers shape their observable teaching work as mediated by their goals for their teaching. These goals are representations of teachers’ epistemological commitments apropos of teaching mathematics, whether those commitments be consciously espoused or unconsciously reproduced due to constraints within which they work. In this chapter, we survey the literature on lesson planning, assessment, and reflection according to eight epistemological paradigms that are widely known in the field of mathematics teaching. These epistemological paradigms are: Situated Learning Theory, Behaviorism, Cognitive Learning Theory, Social Constructivism, Structuralism, Problem Solving, Culturally Relevant Pedagogy, and Project- and Problem-Based Learning. We situate other perspectives on learning theory, which are derivatives of these prevailing paradigms, within this overarching frame. Our literature search revealed that some of the theoretical perspectives are well-reported in the literature whilst others have not received the same amount of attention from researchers. We detail each perspective, providing a definition, goals for teaching, pros and cons, and examples from the literature. We posit that, with the advent of the digital era of mathematics education, researchers must engage more explicitly with the theoretical perspectives we identified as underserved and must reckon with their own epistemological commitments more intentionally when reporting on studies regarding Type D.
Student Mathematics Learning Outcomes
Authors: Radišić Jelena
Published: August 2023

The research focused on the student (learning) outcomes captured upon completion of mathematics teaching is the end goal of presage-process–product research. Student learning outcomes are generally agreed upon as representing the ultimate purpose of teaching and the final criterion on which any assessment of ‘good’ teaching is based. Traditionally, student outcomes are seen as changes in students’ understanding of mathematics, here as measured in a school-based or external evaluation, both nationally and internationally. However, what is measured is primarily influenced by how the outcome is conceptualised. This chapter will discuss the very idea of student outcomes, their assessment and the assessments’ purpose. In addition, we observe the intake of technology in this process, revisiting the notion of outcomes from the lifelong learning perspective and demands of society today.
Individual Student Characteristics, Abilities and Personal Qualities and the Teacher’s Role in Improving Mathematics Learning Outcomes
Authors: Faragher Rhonda M.
Published: August 2023

Teachers of students in general mathematics classrooms accept and welcome the learners they are assigned to teach. The characteristics of students influence the planning teachers undertake, the learning activities they provide, and the learning outcomes achieved by their students as a result. This chapter explores the impact of student characteristics that are beyond the control of teachers, and yet are within their powers through their actions to make a considerable difference to the mathematics learning outcomes of their students. In recent times, two significant developments—the recognition of streaming as harmful and the recognition of inclusive education as beneficial—have changed the nature of general mathematics classrooms. In practice, these developments mean that teachers can expect to teach students across the breadth of human variation. Addressing an area of research focused on units of analysis that are not under the direct control of a teacher, this chapter explicitly relates to learners with intellectual disabilities, learning difficulties and learned difficulties in the context of mathematics education research. Intellectual disability and mathematics learning difficulties are learner qualities while learned difficulties are not; these are traits acquired through the course of education, such as mathematics anxiety. Two recent studies of the inclusion in general primary and secondary mathematics classes of students with Down syndrome provide data that is analysed through the lens of the framework of Manizade et al. (2019) and Medley (1987), and expanded in the first chapter of this volume. Type G (individual student traits) variables and their interaction with particularly Type B (Student mathematics learning activities) and A (Student mathematics learning outcomes) are studied. Through this analysis, it is clear that the mathematical experiences teachers plan for their students are adjusted in complex ways. Where teachers provided year-level adjusted mathematics curriculum, students were able to demonstrate learning outcomes aligned with the school year-level and often many years ahead of their deemed level of mathematics accomplishment. As a way out of low attainment, the possibilities of year-level adjusted curriculum is a critical aspect of mathematics education and an imperative of mathematics education research.
Breast cancers as ecosystems: a metabolic perspective
Authors: Martino Flavia , Lupi Mariadomenica , Giraudo Enrico , Lanzetti Letizia
Published: August 2023

Breast cancer (BC) is the most frequently diagnosed cancer and one of the major causes of cancer death. Despite enormous progress in its management, both from the therapeutic and early diagnosis viewpoints, still around 700,000 patients succumb to the disease each year, worldwide. Late recurrency is the major problem in BC, with many patients developing distant metastases several years after the successful eradication of the primary tumor. This is linked to the phenomenon of metastatic dormancy, a still mysterious trait of the natural history of BC, and of several other types of cancer, by which metastatic cells remain dormant for long periods of time before becoming reactivated to initiate the clinical metastatic disease. In recent years, it has become clear that cancers are best understood if studied as ecosystems in which the impact of non-cancer-cell-autonomous events—dependent on complex interaction between the cancer and its environment, both local and systemic—plays a paramount role, probably as significant as the cell-autonomous alterations occurring in the cancer cell. In adopting this perspective, a metabolic vision of the cancer ecosystem is bound to improve our understanding of the natural history of cancer, across space and time. In BC, many metabolic pathways are coopted into the cancer ecosystem, to serve the anabolic and energy demands of the cancer. Their study is shedding new light on the most critical aspect of BC management, of metastatic dissemination, and that of the related phenomenon of dormancy and fostering the application of the knowledge to the development of metabolic therapies.