{"title":"Cross-diffusion-induced instabilities in a cooperative hunting population with Allee effect","authors":"Gourav Mandal, Lakshmi Narayan Guin, Santabrata Chakravarty","doi":"10.1140/epjp/s13360-025-06017-5","DOIUrl":"10.1140/epjp/s13360-025-06017-5","url":null,"abstract":"<div><p>The spatiotemporal complexity of a system of interacting species, influenced by hunting cooperation and the additive Allee effect, has garnered significant attention within the ecological framework. This study investigates whether interactions among species can stabilize the dynamics of environmental communities and promote coexistence, employing a cross-diffusion-driven species interaction model. The local and global bifurcation behaviour of the proposed system and the stability of all potential equilibrium points in the absence of diffusion have been comprehensively examined. Numerical simulations have been conducted to validate the analytical findings and assess the applicability of the cross-diffusive model. In a two-dimensional plane, the evolution of diffusion-driven pattern generation, known as black-eye replication, around the coexistence equilibrium point has been presented. Furthermore, it has been demonstrated that species interactions within the context of cross-diffusion can exacerbate the instability dynamics of ecological populations by generating spatial patterns. The results underscore the crucial role of cross-diffusion-driven instability in maintaining ecosystem diversity and structure.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143107852","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Estimation of radiological hazards to lungs and some organs due to soil gas radon, thoron, and their progeny using CR-39 polymer detector in Kadhimya, Baghdad, Iraq","authors":"Raghad S. Mohammed, Rasha S. Ahmed","doi":"10.1140/epjp/s13360-025-06045-1","DOIUrl":"10.1140/epjp/s13360-025-06045-1","url":null,"abstract":"<div><p>Naturally occurring radioactive gases like radon and thoron in soil are well known to impact air quality, influencing the resident’s health in that area. This work measured radon and thoron concentrations in soil and the associated radiation hazard indices using CR-39 detector in Kadhimya, Baghdad, Iraq. The mean radon and thoron concentrations in the area under study were determined to be 295.06 ± 4.00 and 1557.2 ± 29.23 Bq/m<sup>3</sup>, respectively. The average indoor and outdoor annual effective dose, the excess lifetime cancer risk, and lung cancer cases per year per million people due to radon were found to be 7.44 ± 0.10 mSv/y<span>(,)</span> 1.86 ± 0.03 mSv/y, 3.58 ± 0.05, and (167.49 ± 2.27<span>()times {10}^{-6})</span>, respectively, and due to thoron, they were found to be 39.29 ± 0.74 mSv/y, 9.82 ± 0.18 mSv/y, 18.91 ± 0.35, and (883.94 ± 16.59<span>()times {10}^{-6})</span>, respectively. The average annual effective dose to lungs due to exposure to radon was estimated to be 148.88 ± 2.02 mSv/y. The average effective dose in tracheobronchial and pulmonary + pulmonary lymph region, and the effective dose in lungs were found to be 8.93 ± 0.12 mSv/y, 8.93 ± 0.12 mSv/y, and 17.87 ± 0.24 mSv/y, respectively. The total effective equivalent dose caused by radon, thoron, and their progeny tissues ranged from 5.62 to 49.45, with an average value of 15.60 mSv/year. All the evaluated radiation hazard indices exceeded the recommended limits of radiation protection agencies. Radon and its progeny contribute about (44%) to the total annual inhalation dose, whereas thoron and its progeny contribute about (56%) to the total annual inhalation dose. The surpassing of recommended radiation hazard limits for radon and thoron highlights the need for regulatory actions and public health interventions.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Amylopectin extraction from kernels as a sustainable additive for enhancing the performance of natural hydraulic lime mortar for restoration applications","authors":"Nisha Sankar, Ravi Ramadoss","doi":"10.1140/epjp/s13360-025-06019-3","DOIUrl":"10.1140/epjp/s13360-025-06019-3","url":null,"abstract":"<div><p>This article presents an innovative study that experimentally investigates the role of amylopectin, extracted from kernels, on the mechanical, physical, and durability properties of natural hydraulic lime (NHL) mortars. Polysaccharides of amylopectin play a major role in increasing the workability of the additive-modified mortar. The amylopectin-modified mortar enhances its compressive strength by 1.68 times compared to the reference mortar. The amylopectin-modified mortar improves its mechanical properties without compromising water absorption and porosity, thus preserving the breathability of the restoration mortar. Amylopectin enhances the hydrophobic property of NHL mortar, forming an outer layer that is resistant to water and salt deposition. The modified mortar’s moisture-holding capacity improves carbonation and reduces drying shrinkage. The polysaccharides of amylopectin enhance the carbonation, regulate the growth of calcite crystals, and result in a denser microstructure, leading to enhanced strength gain. We have also studied the microstructure and morphology characteristics of the modified mortar using XRD, FT-IR, and SEM. We can further extend the investigation to examine the crack capacity of this amylopectin-modified NHL mortar.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sarah Sabah Aljelawy, Ehssan Al-Bermany, Ali Razaq Abdulridha
{"title":"Opto-electrical dielectrics and conductivity behavior of vinyl polymers reinforced with chitosan@graphene oxide nanomaterials for optoelectronic and biological activity","authors":"Sarah Sabah Aljelawy, Ehssan Al-Bermany, Ali Razaq Abdulridha","doi":"10.1140/epjp/s13360-025-06006-8","DOIUrl":"10.1140/epjp/s13360-025-06006-8","url":null,"abstract":"<div><p>Polymer composites are an interesting project for optical devices and medical applications. The influence of modified graphene oxide (GO) nanosheets with nano-chitosan (NCS) nanomaterials on two vinyl polymers was investigated. Polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), and polyacrylic acid (PAA) reinforced with nanomaterials to fabricated PVA-PAA/GO@NCS and PVP-PAA/GO@NCS composites. Strong interfacial interaction exhibited by Fourier-transform infrared spectroscopy. X-ray diffraction showed a semi-crystalline structure. A fine dispersion of nanomaterials was exhibited by image scanning electron microscopy. Optical and transmission electron microscopy revealed the PVA composite’s core–shell formulation, whereas the PVA composite and shrimp shell behavior of PVP composites. The dielectric constant results reduced from 18 to 10.36 for PVA composites and 10.4 to 9.3 for PVP composites. For the dielectric loss, the results enhanced from 15.50 to 1.79 and 2 to 1.4, respectively. The real and imaginary optical dielectric constants improved significantly compared with blended polymers, and composites with PVP presented better results than composites with PVA. In the PVA, the electrical conductivity of composites was enhanced compared to that of the PVP group. Interestingly, PVA nanocomposites revealed a better cytotoxic impact of up to 80% instead of 56% of PVP composites of anti-breast cancer (MTTassa). These interesting findings presented interesting materials for optoelectronic and biological applications.</p><h3>Graphic abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alaa Nihad Tuama, Muhammad Hasnain Jameel, Laith H. Alzubaidi, Zahraa N. Salman, Khalid Haneen Abass, Fouad Sh Hashim, Karar Abdali
{"title":"Enhanced photocatalytic water-splitting performance of innovative silicon carbide (SiC) via suppression of photocorrosion and self-oxidation: a mini-review","authors":"Alaa Nihad Tuama, Muhammad Hasnain Jameel, Laith H. Alzubaidi, Zahraa N. Salman, Khalid Haneen Abass, Fouad Sh Hashim, Karar Abdali","doi":"10.1140/epjp/s13360-025-06043-3","DOIUrl":"10.1140/epjp/s13360-025-06043-3","url":null,"abstract":"<div><p>Over the past few decades, there has been an increasing trend toward researching novel photocatalysts for water splitting and protecting the environment from pollution using sunlight. One approach promising for converting solar energy into sustainable hydrogen fuel is solar water splitting using silicon carbide photocatalyst. SiC nanostructures have garnered much attention from researchers due to their unique chemical and physical characteristics for solar-water-splitting applications. Water splitting with the use of solar energy is a clean, environmentally beneficial method that can help overcome the energy issue and make a big contribution to environmental preservation. The development, difficulties, and prospects of employing SiC for water-splitting-based hydrogen production are covered and summarized in this paper. Moreover, self-oxidation, photocorrosion, and electron–hole recombination have all been used to analyze SiC’s photocatalytic performance.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Double exponential smoothing slime mould algorithm for disease detection in IoT healthcare system","authors":"Tzu-Chia Chen","doi":"10.1140/epjp/s13360-025-06032-6","DOIUrl":"10.1140/epjp/s13360-025-06032-6","url":null,"abstract":"<div><p>This paper presents an algorithm, called the double exponential smoothing slime mould algorithm (DeSSMA), which is formulated to train deep learning models for the precise detection of diseases in patients. The DeSSMA is designed by integrating the principles of double exponential smoothing with the slime mould algorithm. The parameters, including energy depletion, link lifetime (LLT), and distance, are considered by the proposed DeSSMA as objectives aimed at optimizing data routing efficiency. In the base station, a deep residual network (DRN) is trained using the proposed DeSSMA algorithm, which is utilized for disease detection following the processes of data preprocessing, augmentation, and feature selection. Finally, performance evaluation of the DeSSMA-DRN framework is conducted using metrics such as energy consumption, LLT, accuracy, sensitivity, specificity, and receiver operating characteristic. The findings reveal that the proposed framework achieved a minimal energy depletion rate of 0.412 (J), an LLT rate of 0.318, an increased accuracy rate of 0.959, a high sensitivity rate of 0.967, and a specificity rate of 0.931.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mridusmita Das, Murchana Khusroo, Madhurjya P. Bora
{"title":"Fast-moving electrostatic solitons in a plasma with turbulence heating","authors":"Mridusmita Das, Murchana Khusroo, Madhurjya P. Bora","doi":"10.1140/epjp/s13360-025-06005-9","DOIUrl":"10.1140/epjp/s13360-025-06005-9","url":null,"abstract":"<div><p>In this work, it is shown that electrostatic solitons in a plasma with turbulent heating of the electrons through an accelerating electric field can form with very high velocities, reaching up to several order of magnitudes larger than the equilibrium ion-sound speed. The possible parameter regime, where this work may be relevant, can be found in the so-called dead zones of a protoplanetary disk. Though these zones are stable to magnetorotational instability, the resultant turbulence can in fact heat the electrons making them follow a highly non-Maxwellian velocity distribution. We show that these fast-moving solitons can reach very high velocities. With electron velocity distribution described by the Davydov distribution function, we argue that these solitons can be an effective mechanism for energy equilibration in such a situation through soliton decay and radiation.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improved resistive switching behaviour in Ag–ZrO2 nanocomposite film","authors":"Aman Sharma, Mohd Faraz, Neeraj Khare","doi":"10.1140/epjp/s13360-025-06018-4","DOIUrl":"10.1140/epjp/s13360-025-06018-4","url":null,"abstract":"<div><p>The resistive switching behaviour and nonvolatile memory effects in zirconium oxide (ZrO<sub>2</sub>) and silver nanoparticles (AgNP)-ZrO<sub>2</sub> nanocomposite films have been studied. To explore the role of adding AgNP in resistive switching of the nanocomposite films, fluorine-doped tin oxide (FTO)/AgNP-ZrO<sub>2</sub>/silver (Ag) trilayer structure has been fabricated by spray coating of AgNPs-ZrO<sub>2</sub> on FTO with varying AgNP content in the nanocomposite film. X-ray diffraction (XRD) analysis confirms the single-phase ZrO<sub>2</sub> structure, with no additional peaks corresponding to AgNP due to its low concentration. Current (I)–voltage (V) measurement shows a decrease in switching voltage from 1.8 V for the pure ZrO<sub>2</sub> to 0.38 V for 1 wt% AgNP-ZrO<sub>2</sub> nanocomposite film. The cyclic I-V measurement shows an increase in the on–off ratio from 22 for pure ZrO<sub>2</sub> to 32 for 1 wt% AgNP-ZrO<sub>2</sub> nanocomposite devices. The retentivity measurement shows distinct on–off values for pure ZrO<sub>2</sub> and AgNP-ZrO<sub>2</sub> nanocomposite films over time. The temperature-dependent resistivity (R-T) measurements reveal that all devices (pure ZrO<sub>2</sub>, 0.5 wt% AgNP-ZrO<sub>2</sub>, and 1 wt% AgNP-ZrO<sub>2</sub>) exhibit semiconducting behaviour in the high-resistance state, with activation energy decreasing from 87.1 to 48.43 meV as AgNP content increases. In the low-resistance state, all devices show metallic-like conduction. Additionally, the temperature coefficient of resistance (<i>α</i>) increases from 3.54 × 10<sup>–3</sup> K<sup>−1</sup> to 5.15 × 10<sup>–2</sup> K<sup>−1</sup> with higher AgNP concentration. The value of <i>α</i> is increased for AgNP-ZrO<sub>2</sub> nanocomposite compared to the ZrO<sub>2</sub> device, suggesting that in pure ZrO<sub>2</sub>, only oxygen vacancies were involved, whereas, in AgNP-ZrO<sub>2</sub> nanocomposite, both oxygen vacancies and Ag metal nanoparticles participate in the formation of conducting filaments.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><img></picture></div></div></figure></div></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Phenomenology of the dark matter sector in the 2HDM extended with complex scalar singlet","authors":"Juhi Dutta, Gudrid Moortgat-Pick, Merle Schreiber","doi":"10.1140/epjp/s13360-025-06015-7","DOIUrl":"10.1140/epjp/s13360-025-06015-7","url":null,"abstract":"<div><p>The two-Higgs-doublet model augmented with a complex scalar singlet (2HDMS) is a well-motivated candidate for Beyond Standard Model (BSM) Physics. We investigate the dark matter phenomenology of the 2HDMS with the complex scalar singlet as the dark matter candidate. We perform a study of the parameter space allowed by existing theoretical and experimental constraints from dark matter, flavour physics and collider searches. Further, we discuss a few benchmark scenarios to test the discovery potential for the 2HDMS at the HL-LHC and at future high-energy <span>(e^+e^-)</span> colliders.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06015-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143110002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Investigating the differences in the optical properties and laser photoluminescence for chitosan films extracted from two different origins","authors":"Ahmed R. Ghazy","doi":"10.1140/epjp/s13360-025-06021-9","DOIUrl":"10.1140/epjp/s13360-025-06021-9","url":null,"abstract":"<div><p>This work carefully examines the variations in chitosan films derived from shrimp and crab shells in terms of their optical characteristics and laser-induced photoluminescence. Chitosan was dissolved in acetic acid and then cast into films to create chitosan films. The functional properties of chitosan generated from crab and prawns were shown to differ in specific spectrum regions due to differences in hydrogen bonding, degree of deacetylation, and structural conformations, as indicated by the FTIR study. Using TD-DFT and TD-DFT/CASTEP simulations, computational studies were carried out to predict the chitosan samples' molecular structures and frequency characteristics. Measurements and analyses were done on the optical characteristics, such as absorbance, refractive index, dielectric constants, and optical conductivity. Chitosan from shrimp shells (chitosan 2) and crab shells (chitosan 1) differed significantly in terms of UV absorbance, refractive index, dielectric constant, and optical conductivity, according to the study. Chitosan 2 showed increased dielectric constant, refractive index, and UV absorbance, indicating higher optical conductivity and a larger capacity for electrical energy storage, making it a better fit for optoelectronic applications. Chitosan's optical and photoluminescence characteristics are greatly influenced by its place of origin. These results emphasize how crucial it is to choose the right source material for a given optical application, especially in domains, where precise control over UV absorption and refractive index is necessary.</p></div>","PeriodicalId":792,"journal":{"name":"The European Physical Journal Plus","volume":"140 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1140/epjp/s13360-025-06021-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143109980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}