bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanistic insights into pH-sensitive photoluminescence of carbon dots: The role of carboxyl group
Authors: Zhou Yujie , Ye Chunyin , Zhang Jiachen , Jiang Shenlong , Zhang Qun
Published: December 2024

We present a mechanistic study of pH-sensitive photoluminescence (PL) in two deliberately designed systems of carbon dots (CDs), which are relatively poor and rich in carboxyl groups anchored on their surfaces, denoted CDs-COOH(p) and CDs-COOH(r), respectively. The underlying PL mechanisms for the two contrasting CD systems are revealed to be different. As for CDs-COOH(p), the pH response of PL exhibits an asymmetric volcano-shaped pattern featuring dynamic and static quenching under acidic and alkaline conditions, dominated by the effects of hydrogen bonding and non-emissive ground-state complex, respectively. As for CDs-COOH(r), however, the pH response exhibits an interesting sigmoid-shaped pattern featuring PL quenching under acidic conditions but PL enhancement under alkaline conditions, both of which become more pronounced with increasing photoexcitation energy, exhibiting a nearly symmetric trumpet-shaped pattern. Such patterns of PL response to acidity/alkalinity and photoexcitation energy can be understood in terms of the prominent effect of excited-state proton transfer that is coupled to the surface emissive centers of the carboxyl group and can be effectively modulated via pH-regulated protonation/deprotonation. Our comparative analyses of the pH-regulated surface-sensitive PL quenching/enhancement behaviors in the two CD systems allow for elucidating the different surface-state-controlled PL mechanisms, highlighting the specific role of carboxyl groups in the pH-sensitive PL of CDs. The mechanistic insights gleaned from this work would be useful for CDs-based applications such as luminescence, sensing, and bioimaging.
Effects of fructo-oligosaccharides and Bacillus licheniformis on performance, nutrient digestibility, hematological properties, and organ development in weaned piglets
Authors: Wu Fan , Wu Di , Chen Zhihui , Ren Fengyun
Published: December 2024

Context Weaning is a critical period for piglets, often associated with reduced growth performance and increased susceptibility to diseases. Dietary supplements such as fructo-oligosaccharides (FOS) and Bacillus licheniformis (BL) may improve piglet health and performance during this transition. Aims To investigate the effects of dietary FOS and BL supplementation, individually and in combination, on growth performance, health status, nutrient digestibility, hematological parameters, and organ development in weaned piglets. Methods In total, 240 weaned piglets were allocated into the following six treatments: control, 0.2% FOS, 0.4% FOS, BL, 0.2% FOS + BL, and 0.4% FOS + BL. Growth performance, morbidity rates, nutrient digestibility, blood parameters, and organ indices were evaluated over the experimental period. Key results The 0.4% FOS + BL group showed significant improvements in feed conversion ratio, reduced morbidity rates, enhanced nutrient digestibility (crude protein, crude fiber, and phosphorus), increased total protein, albumin, and albumin:globulin ratio, reduced blood urea nitrogen, improved white blood cell and lymphocyte counts, and enhanced spleen and pancreatic organ indices. BL supplementation distinctively influenced liver-enzyme profiles, suggesting metabolic adaptation rather than hepatic stress. Blood urea nitrogen was reduced in BL and 0.4% FOS + BL groups. Conclusions Dietary supplementation with 0.4% FOS and BL synergistically benefited weaned piglets by improving growth performance, enhancing feed efficiency, and reducing morbidity rates. This treatment also enhanced nutrient utilization, positively affected blood parameters, and promotes the development of spleen and pancreatic organs. Implications The combination of 0.4% FOS and BL shows potential as an effective feed-additive strategy to enhance growth and immune responses in weaned piglets, potentially reducing the need for antibiotics and promoting sustainable pig production.
Exploration of factors of algal seasonal blooms in a drinking-water source
Authors: Yan Ailan , Qian Feilai , Li Yande , Qian Dongsheng , Chen Yongfei , Xu Dong
Published: December 2024

Context The emergence of cyanobacterial blooms has garnered international concern especially during seasonal transitions. Aims The objective of this study is to investigate the primary correlation factors contributing to algal blooms through an examination of the relationship between nutrient distribution and seasonal algae growth, specifically in the context of low nitrogen and phosphorus concentrations in the source of drinking water. Methods By monitoring water-quality indicators over a 6-month period, including total nitrogen, total phosphorus, ammonia nitrogen, water temperature, pH value and phytoplankton content, the dynamic trend of algal growth was evaluated, and the primary factors contributing to algal outbreaks were analysed. Key results The findings indicated a significant correlation between algae blooms and elevated water temperature and light intensity in Shuangxikou Reservoir. As light intensity and water temperature increased, there was a shift in dominant algae species from Bacillariophyta to cyanobacteria. Conclusions Algal biomass was primarily concentrated at depths between 0 and 4 m, leading to a higher pH value in this specific water area than in the other areas along the vertical axis as a result of the algal outbreak. Implications This study has made a substantial contribution to the identification of safe methods for managing seasonal algae growth.
Sexual dissatisfaction and its association with health status among older adults in China: a nationwide study
Authors: Diao Yiwen , Sun Yan , Tucker Joseph D. , Yang Fan
Published: December 2024

Background Most population-based sexual health research in China excludes older adults. To fill the gap, this study aims to characterise sexual dissatisfaction among people aged 50 years or older from a nationwide, population-representative sample and to explore its association with physical, mental, and self-reported overall health indicators. Methods Data were collected as part of the China Family Panel Studies in 2020, led by the Institute of Social Science Survey of Peking University. Multivariable logistic regressions with robust estimators were used to investigate the association between sexual dissatisfaction and health indicators and potential demographic confounders. Results Among the 8222 partnered Chinese adults aged 50 years or older (median age: 59, IQR: 54–66, 47% identified as women), 78% (6380/8222) reported being satisfied or very satisfied in their sex life. After adjusting for demographic variables, poor self-rated health status (aOR: 1.59, 95% CI: 1.42–1.77), experiencing depression symptoms (aOR: 2.02, 95% CI: 1.80–2.26), and having chronic diseases (aOR: 1.20, 95% CI: 1.07–1.36) were positively associated with sexual dissatisfaction in multivariable analyses. Among sociodemographic factors, younger age, female gender, and education level at senior high school or above were more likely to experience sexual dissatisfaction (all P < 0.05). Conclusion Based on our sample, more than one in five Chinese adults aged 50 years or older might face sexual dissatisfaction. Comorbidities common in older age likely exacerbate sexual dissatisfaction. Greater attention to sexual satisfaction research and sexual health programs among older adults is needed with respect to gender differences and chronic disease comorbidities.
The elusive nature of Martian liquid brines
Authors: Chevrier Vincent F. , Slank Rachel A.
Published: December 2024

The possible presence of brines on Mars adds an intriguing dimension to the exploration of Martian environments. Their potential involvement in the formation of recurring slope lineae has sparked debates on the existence of liquid water versus alternative dry processes. In situ instrumentation on rovers and landers has been instrumental in providing valuable data for comprehending the dynamics of brines. Laboratory experiments and thermodynamic simulations conducted under Martian conditions offer insights into the formation and persistence of brines, shedding light on the planet’s current hydrological processes. Despite these findings, the prevailing surface conditions on Mars, characterized by a combination of low temperature, pressure, and water vapor pressure, generally hinder the stability of most brines. In such environments, only a few select salts, notably calcium perchlorate, could play a pivotal role in potentially forming brines through deliquescence or melting. These environmental factors emerge as critical contributors influencing the stability of brines, but such limitations generally restrict the locations, timescales, and amounts of brine formed. However, the exploration of brines extends beyond geochemical considerations, serving as a lens through which we can examine potential habitability and gain a broader understanding of the Martian climate. Therefore, observing brines on Mars would offer valuable insights into the dynamic interplay of various factors that influence their stability, contributing to our overall comprehension of Mars’ unique environmental conditions.
Cyanobacteria–probiotics symbionts for modulation of intestinal inflammation and microbiome dysregulation in colitis
Authors: Yang Jiali , Tan Shaochong , Ge Shengchan , Yang Mingzhu , Liu Hua , Liu Wei , Zhang Kaixiang , Zhang Zhenzhong , Wang Zhi-Hao , Shi Jinjin , Liu Junjie
Published: December 2024

Inflammatory bowel disease (IBD) is often associated with excessive inflammatory response and highly dysregulated gut microbiota. Traditional treatments utilize drugs to manage inflammation, potentially with probiotic therapy as an adjuvant. However, current standard practices often suffer from detrimental side effects, low bioavailability, and unsatisfactory therapeutic outcomes. Microbial complexes characterized by mutually beneficial symbiosis hold great promise for IBD therapy. Here, we aggregated
Synechocystis
sp. PCC6803 (Sp) with
Bacillus subtilis
(BS) by biomimetic mineralization to form cyanobacteria–probiotics symbionts (ASp@BS), which reshaped a healthy immune system and gut microbiota in a murine model of acute colitis. The symbionts exhibited excellent tolerance to the harsh environment of the gastrointestinal tract. Importantly, probiotics within the symbionts created a local anaerobic environment to activate the [NiFe]-hydrogenase enzyme of cyanobacteria, facilitating the production of hydrogen gas (H
2
) to persistently scavenge elevated reactive oxygen species and alleviate inflammatory factors. The resulting reduced inflammation improves the viability of the probiotics to efficiently regulate the gut microbiota and reshape the intestinal barrier functions. Our research elucidates that ASp@BS leverages the synergistic interaction between Sp and BS to create a therapeutic platform that addresses multiple aspects of IBD, offering a promising and comprehensive solution for IBD treatment.
Nocturnal camouflage through background matching against moonlight
Authors: Negro Juan J. , Bará Salvador , Galadí-Enríquez David , Nieves Juan Luis , Martínez-Domingo Miguel A. , Ferrero Alejandro , Campos Joaquín , Bao-Varela Carmen , Masana Eduard , Camacho Carlos
Published: December 2024

Camouflage is often considered a daytime phenomenon based on light and shade. Nocturnal camouflage can also occur, but its mechanistic basis remains unclear. Here, we analyze the conditions for background matching (BM) of avian predators against the night sky. Such concealment is achieved when the contrast between the predator and the sky is smaller than the contrast detection threshold of prey. This condition cannot be fulfilled under isotropic skies, as in fully overcast or moonless nights. However, on clear moonlit nights, the isotropy of the sky radiance is broken due to the presence of the Moon, and the conditions for BM can be met for a wide range of sky directions. This effect is mainly dependent on the altitude of the Moon above the horizon, rather than on Moon phase. We have modeled the feasibility of concealment through BM of a typically white barn owl (
Tyto alba
) when hunting rodents, based on its contrast against the moonlit sky. We considered the radiometric quantities of the sky, the ground, and the bird’s undersides. Our results show that a barn owl with highly reflecting underparts may approach a rodent from broad regions of the moonlit sky while keeping itself below the contrast detection threshold of the mouse M-cones and rods. S-cones, in turn, remain below their excitation threshold for most of the lunar cycle. Our results demonstrate that the white color of barn owls serves as camouflage tailored to the moonlit sky background, providing a mechanistic basis for understanding nocturnal camouflage.
Cold-blooded vertebrate utilizes behavioral fever to alleviate T cell apoptosis and optimize antimicrobial immunity
Authors: Gao Haiyou , Wei Xiumei , Li Kang , Cao Yi , Rao Wenzhuo , Zhang Jiansong , Wang Ding , Yang Jialong
Published: December 2024

Fever confers significant survival benefits on endotherms by optimizing both innate and adaptive immunity. Ectotherms achieve thermoregulation using behavioral strategies, but existing evidence supports its enhancement effect on innate immunity only. Therefore, it remains unknown whether the coordination between fever and adaptive immunity was independently acquired by endotherms or instead represents a gradually evolved function common to vertebrates. In the present study, we reported that Nile tilapia developed behavioral fever to enhance the immune response against
Edwardsiella piscicida
infection. Behavioral fever lasted five days, and the immune potential was optimized at 4 to 6 d post infection, indicating a potential correlation between fever events and T cell immunity. Further investigation suggested that fever did not affect T cell activation or proliferation but improved the ability of T cells to produce IFN-γ and Granzyme B and enhanced cytotoxicity, thereby eliminating the infection more effectively. Notably, we identified an advantage conferred by fever during infection: alleviation of T cell apoptosis to maintain a considerable T cell pool. Mechanistically, fever induced the expression of HSP70, which in turn entered the nucleus and bound to and promoted the phosphorylation of ERK1/2, thereby inhibiting the cleavage of caspase-8/caspase-3 and preventing T cell apoptosis. Our findings elucidate the detailed mechanism by which behavioral fever optimizes T cell immunity in a cold-blooded vertebrate and propose that integrating fever with adaptive immunity to gain survival advantages is an ancient strategy acquired before the emergence of tetrapod.
The benefits of removing toxic chemicals from plastics
Authors: Cropper Maureen , Dunlop Sarah , Hinshaw Hudson , Landrigan Philip , Park Yongjoon , Symeonides Christos
Published: December 2024

More than 16,000 chemicals are incorporated into plastics to impart properties such as color, flexibility, and durability. These chemicals may leach from plastics, resulting in widespread human exposure during everyday use. Two plastic-associated chemicals—bisphenol A (BPA) and di(2-ethylhexyl) phthalate (DEHP)—and a class of chemicals—brominated flame retardants [polybrominated diphenyl ethers (PBDEs)]—are credibly linked to adverse health and cognitive impacts. BPA exposures are associated with ischemic heart disease (IHD) and stroke, DEHP exposure with increased all-cause mortality among persons 55 to 64 y old, and prenatal PBDE exposures in mothers with IQ losses in their children. We estimate BPA, DEHP, and PBDE exposures in 38 countries containing one-third of the world’s population. We find that in 2015, 5.4 million cases of IHD and 346,000 cases of stroke were associated with BPA exposure; that DEHP exposures were linked to approximately 164,000 deaths among 55-to-64 y olds; and that 11.7 million IQ points were lost due to maternal PBDE exposure. We estimate the costs of these health impacts to be $1.5 trillion 2015 purchasing power parity dollars. If exposures to BPA and DEHP in the United States had been at 2015 levels since 2003, 515,000 fewer deaths would have been attributed to BPA and DEHP between 2003 and 2015. If PBDE levels in mothers had been at 2015 levels since 2005, over 42 million IQ points would have been saved between 2005 and 2015.
Allee effects limit coral fertilization success
Authors: Mumby Peter J. , Sartori Greta , Buccheri Elizabeth , Alessi Cinzia , Allan Hannah , Doropoulos Christopher , Rengiil Geraldine , Ricardo Gerard
Published: December 2024

Coral populations are being progressively thinned by climate change, which elevates the risk of reproductive failure from Allee effects during fertilization. Studies have shown that fertilization success improves during more intense and synchronized spawning, but the local dependence of fertilization on coral density remains unknown in wild populations. Here, we measure the fertilization success of individual colonies of the common table coral,
Acropora hyacinthus
in Palau, Micronesia. We find strong evidence of spatial Allee effects such that fertilization averaged 30% when colonies were in close proximity (<0.5 m), but this declined rapidly to less than 10% at a separation of 10 m and virtually zero by 15 to 20 m. The distance of a nearest neighbor conspecific, gravid colony is a better predictor of observing Allee effects than local colony density measured at several alternative scales (2 to 10 m). Spawning synchrony increases when corals are in close proximity, which may reinforce Allee effects as reproductive colonies become further separated. Fertilization success declined nearly threefold on a second night of spawning with higher wind despite there being more intensive spawning of colonies, highlighting the potential importance of prevailing weather in driving the outcome of mass spawning events. Overall, we find that the local population of
A. hyacinthus
achieved 71% of its fertilization potential. Further studies of spatial patchiness in coral populations are needed to generalize the likelihood of Allee effects, how climate change impacts reproductive function on reefs, and opportunities for restoration to safeguard reproductive success by reconnecting depleted coral populations.
Children’s literature in translation
Authors: Odber De Baubeta Patricia Anne
Published: December 2024

This paper considers an early international publishing franchise, in which titles published in French by Gautier-Languereau for their children’s Série 15 were purchased by foreign publishing houses, translated, then marketed in Portugal, Spain and Italy. The books contain short stories (15 in each) that may originally have been intended for adult readers but have now been appropriated by literary editors for a juvenile audience, thus moving into the category of ‘crossover’ fiction. In some cases, the original story was published in English, translated into French, then re-translated from French into Portuguese or Spanish, hence the term ‘double crossing’. This process raises a number of questions about the nature of intercultural transfer, children’s responses – or responsiveness – to foreign literature, and the status accorded to children’s literature in general. An examination of some of the Portuguese translations seems to corroborate Zohar Shavit’s view (1999) that translators working with a supposedly minor or peripheral genre do not hesitate to modify or adapt their source text. While purists might wish to accuse the translator of committing an act of betrayal, as in the time-honoured adage traduttore, traditore, there is no evidence to suggest that the youthful readers of the Portuguese Série 15 felt especially defrauded or cheated in their reading experience, a reaction which may bear out Paul Hazard’s (1960) belief in a universal republic of children. Nowadays there is a great deal of theorising of children’s literature, much of it by educationalists or ‘mediadores’, some from a feminist perspective, some from the perspective of translation and cultural studies. Scholars have made in-depth studies, written essays and monographs, contributed articles to encyclopaedias and histories of children’s literature, and tackled a broad range of issues
The influence of uppercase letter location on typing multiword passphrases
Authors: Gow Keira , Taikh Alexander , Islam Morshedul
Published: December 2024

Organizational policies for passwords and passphrases require certain criteria, such as minimum length or
uppercase letters, to be met, often resulting in a tradeoff between complexity and ease of typing. Uppercase letters,
specifically, lead to slower and more error prone entries. Our present study examined their influence on the typing of three-word
passphrases. We were interested in whether uppercase letter location, which should not influence passphrase security, would
influence its typing. Passphrases with no uppercase letter were typed more accurately and quickly than passphrases with an
uppercase letter. Importantly, passphrases with an uppercase letter in the second word were more likely to be typed incorrectly,
and were typed more slowly when entered correctly. Our findings are consistent with the linguistic information of adjacent words
influencing the output of the word being typed, where an altered second word interfered with the output of both the first and
second words.
Identification of the Polo-like kinase substrate required for homologous synapsis
Authors: Gold Ariel L. , Hurlock Matthew E. , Guevara Alicia M. , Isenberg Lilah Y.Z. , Kim Yumi
Published: December 2024

The synaptonemal complex (SC) is a zipper-like protein structure that aligns homologous chromosome pairs and regulates recombination during meiosis. Despite its conserved appearance and function, how synapsis occurs between chromosome axes remains elusive. Here, we demonstrate that Polo-like kinases (PLKs) phosphorylate a single conserved residue in the disordered C-terminal tails of two paralogous SC subunits, SYP-5 and SYP-6, to establish an electrostatic interface between the SC central region and chromosome axes in C. elegans. While SYP-5/6 phosphorylation is dispensable for the ability of SC proteins to self-assemble, local phosphorylation by PLKs at the pairing center is crucial for SC elongation between homologous chromosome axes. Additionally, SYP-5/6 phosphorylation is essential for asymmetric SC disassembly and proper PLK-2 localization after crossover designation, which drives chromosome remodeling required for homolog separation during meiosis I. This work identifies a key regulatory mechanism by which localized PLK activity mediates the SC–axis interaction through phosphorylation of SYP-5/6, coupling synapsis initiation to homolog pairing.
Investigating degradation efficiency in plasma reactors through driving frequency optimization
Authors: Winburn Matthew R , Cheung Chin Li
Published: December 2024

Plasma-assisted degradation (PAD) methods have shown promise in water treatment applications, leveraging electrical energy to break down organic contaminants. Here we report our investigation of the driving frequency dependent nature of PAD using a falling-film plasma reactor for the degradation of brilliant blue dye in aqueous solutions. The degradation kinetics of the dye were analyzed and correlated with the energy efficiency, power consumption, and driving frequency of the reactor. Experimental trials revealed that tuning the driving frequency to align with the reactor’s natural resonance significantly enhanced degradation efficiency, achieving an electrical energy per order (E
EO) of nearly 100 kW m−3 at an optimal frequency of 9 kHz. Results indicate a nonlinear relationship between power consumption and frequency, confirming harmonic resonance within the plasma reactor and underscoring the importance of optimizing electrical parameters for cost-effective treatment. An LCR circuit model was used to explain the differences in power consumption across the examined frequency range. This research highlights the potential of driving frequency tuning to optimize the generation of reactive chemical species in PAD methods for organic contaminant degradation. By highlighting how harmonic frequency tuning maximizes reactive species generation, this study provides a foundation for future improvements in PAD systems, offering a pathway to scalable, energy-efficient water treatment technologies.
IHR-Net: image haze removal network based on improved YUV spatial strategy
Authors: Si Yazhong , Li Chen , Yang Fan
Published: December 2024

Image haze removal is a challenging task in computer vision. Existing dehazing algorithms are typically applied in the RGB space, assuming that haze affects all color channels equally, and thus enhancing the image independently across the three channels. Actually, compared to the RGB space, the YUV domain can provide a more accurate representation of haze distribution characteristics and is better suited for image haze removal. Nevertheless, current YUV-based dehazing strategies often suffer from dull colors due to a lack of comprehensive consideration of color channels. To address this limitation, we propose an improved YUV domain-based image haze removal network (IHR-Net), which consists of a pre-trained model and a backbone network to enhance the Y channel and UV channels separately. Specifically, we utilize the pre-trained model to extract haze features that guide the backbone network in optimizing the UV channels. To increase the network’s attention to color-shifting areas, we introduce a haze attention module and integrate it into the backbone network. Experimental results on both synthetic and real-world daytime and nighttime images demonstrate the superior performance of IHR-Net.
Study of friction stir welding effects on the microstructure & mechanical properties of AA3003 pipes
Authors: Sharma Ashish , Khan Zahid A , Siddiquee Arshad Noor , Arif Mohammad
Published: December 2024

In the present study, similar Aluminum (AA3003) alloy pipes with a thickness of 5 mm were friction stir welded using a high-speed steel (HSS) tool with a cylindrical pin profile. Welding was done at three different rotational speeds and three traverse speeds corresponding to pipes of three different diameters. Six combinations of rotational speed and traverse speed were used to observe the effect of energy input on the properties, specifically tensile strength and microhardness, as well as grain size of the resulting microstructure. This systematic variation in welding parameters was designed to assess how changes in energy input influence both the mechanical performance and microstructural attributes of the welded joints. The tensile test results indicated that an ultimate tensile strength (UTS) of 84% relative to the base metal was achieved at a rotational speed of 900 rotations per minute(rpm) and a traverse speed of 131.94 mm/min. The impact energy corresponding to these parameters was found to be 38% more than base metal which is a remarkable contribution. This combination of welding parameters facilitated optimal material flow and bonding, resulting in improved tensile properties of the welded joint. Additionally, the tensile results showed a consistent pattern in the tensile failure of the welded samples, where the joint failure occurred at the location with the lowest hardness in the welded region. This correlation highlights the critical influence of hardness distribution on the structural integrity of the welds, indicating that areas with reduced hardness are more prone to failure under tensile loading of FSWed joints.
Probing an amplified spin-orbit torque effect in antiferromagnetic oxide utilizing a magnetoresistance-based loop-shift method
Authors: Tseng Hsiang-Hsuan , Wu Ting-I , Yang Meng-Chi , Hsieh Cheng-Hsun , Wu Yu-Hui , Yang Chao-Yao
Published: December 2024

Spin transport in antiferromagnets (AFMs) and the resulting spin torque effects have recently aroused significant interest due to their non-trivial physics involving long spin diffusion dynamics and low spin dissipation. Although recent studies have been devoted to focusing on spin transport within AFMs, few have effectively demonstrated the spin torque generated accordingly. This study attempts to correlate spin transport and the associated spin–orbit torque (SOT) effects in a Pt/NiO/CoFeB trilayer with varying NiO thicknesses. The characterization was performed using angle-dependent magnetoresistance (ADMR) measurements and the magnetoresistance (MR)-based loop-shift method in a y-type geometry. It showed varying the NiO thickness in the trilayer allowed tailoring the robustness of NiO to promote the magnon transport through the spin fluctuation dynamics: Inserting an NiO layer of moderate thickness in the trilayer enables enhancing the SOT efficiency by threefold compared to the NiO-free stack. However, further increasing the NiO thickness appeared to reduce the SOT efficiency, as indicated by both ADMR and MR-based loop-shift measurements. The enhanced SOT efficiency quantitatively highlights the significance of AFM oxides for SOT devices together with the issues of spin transport modification, suggesting a pathway to reducing current density to meet low-power consumption SOT device technology.
Parameters identification of magnetorheological damper based on improved grey wolf optimization algorithm
Authors: Li Kangjun , Yang Xiaolong , Li Denghui , Xie Guojin
Published: December 2024

Parameter identification of the mechanical model of magnetorheological dampers is usually carried out through a combination of optimization algorithms, but there is little research on the impact of the optimization algorithm itself on the identification results. In order to improve the accuracy of parameter identification results, the influence of the parameters of the optimization algorithm itself on the fitting results was investigated in this study, and the optimization algorithm adopted the improved grey wolf algorithm. The effects of different wolf pack numbers and iteration times on recognition results were examined in this study. The various parameters in the mechanical model of magnetorheological dampers are determined utilizing the optimal combination of algorithm parameters. Finally, the validity of the identification results was verified by evaluating the consistency between the identified damping force and the experimental damping force. The results indicate that when the optimal combination is used, the accuracy of parameter identification can be improved.
First-Principles insights into ferromagnetic, optoelectronic and dynamical properties of Eu/Er Co-doped AlGaN
Authors: Belhachi Soufyane , Celestine L. , Rai D P , Goumri-Said Souraya
Published: December 2024

In this thorough investigation, we analyze the complex electronic, magnetic, and structural properties of wurtzite-structured aluminum gallium nitride (Al0.125Ga0.75N) when co-doped with the rare-earth elements erbium and europium. Leveraging a modified LSDA+U approach that adeptly captures the pivotal interactions within the 4f shell, our findings unveil that the co-doped AlGaN exhibits distinct semiconducting behavior. Remarkably, in stark contrast to its pristine Al0.125Ga0.75N counterpart, the co-doped material manifests an indirect band gap whose value is notably reduced. This intriguing phenomenon of ferromagnetism observed in the co-doped system can be attributed to the intricate interplay between the f-p and p-d states, culminating in the formation of hybridized f-p-d orbitals. Our investigation further elucidates the intricate hybridization of various orbitals at the valence band maximum (VBM), including the harmonious fusion of p-d orbitals derived from Eu-5d, Er-5d, and N-2p. Notably, the magnetic moment exhibits a pronounced localization at the Eu and Er sites, attaining substantial values of 5.90 μB and 2.99 μB, respectively. Moreover, our comprehensive exploration encompasses the calculation of the real and imaginary components of the dielectric function, refractive index, and extinction coefficient, spanning an impressive photon energy range of up to 12 eV. Significantly, in the ultraviolet region of the optical spectrum, the imaginary part of the Eu and Er co-doped Al0.125Ga0.75N unveils a pronounced absorption coefficient, a pivotal property with far-reaching implications for optoelectronic applications.
Shape-controlled Bose–Einstein condensation
Authors: Kurt Cem , Sisman Altug , Aydin Alhun
Published: December 2024

Size-invariant shape transformation is a geometric technique that allows for a clear separation between quantum size and shape effects by modifying the shape of the confinement domain without altering its size. The impact of shape on the behavior of confined systems is significantly different from that of size, making it an emerging area of research. The recent realization of flat-bottomed optical box traps has further contributed to the study of quantum gases in complex confinement geometries. Here, we propose shape-induced Bose–Einstein condensation at a fixed size, temperature, and density. We investigate the impact of pure quantum shape effects on a non-interacting Bose gas confined within nested square domains, where the shape parameter is defined and controlled by the rotation angle between the inner and outer squares. Our findings reveal that specific heat exhibits an additional low-temperature peak at certain shapes. This work opens new avenues for controlling quantum systems through geometric manipulation and provides insights into the thermodynamic properties of Bose gases under shape-induced quantum effects.
The Electronic Structure, Optical and Magnetic Properties of Cu, Fe, Mn, Ni, and V Doped Bi2WO6 in the Visible Light Region
Authors: Tian Yilong , Xiao Qingquan , Xie Quan , Zhu Yao , Ye Jianfeng , Lu Shengshang
Published: December 2024

The elastic and mechanical properties of intrinsic Bi2WO6 semiconductors, along with the electronic, optical, and magnetic properties of Cu-, Fe-, Mn-, Ni-, and V-doped Bi2WO6 at a uniform doping concentration of 6.25%, are studied using density functional theory (GGA+U). The study shows that intrinsic Bi2WO6 semiconductors exhibit good mechanical stability, anisotropy, and mixed ionic-covalent characteristics (Poisson's ratio ν = 0.17), classifying them as brittle oxide materials (B/G ≈ 0.8). Compared to intrinsic Bi2WO6, the doped Bi2WO6 exhibits a narrower bandgap, a broader absorption spectrum, and higher optical sensitivity. Their optical properties in the visible light range surpass those of intrinsic Bi2WO6, making them more promising for use as semiconductor catalysts. Notably, Cu- and V-doped Bi2WO6 exhibit higher absorption coefficients in the visible light region compared to other element-doped Bi2WO6, with a broader absorption spectrum and more pronounced photocatalytic effects. Furthermore, Cu-, Fe-, Mn-, Ni-, and V-doped Bi2WO6materials exhibit characteristics of diluted magnetic semiconductors, The total magnetic moments are 1.793 μB (Bi1.9375Cu0.0625WO6), 3.086 μB (Bi1.9375Fe0.0625WO6), 3.823 μB (Bi1.9375Mn0.0625WO6), 1.257 μB (Bi1.9375Ni0.0625WO6), and 1.859 μB (Bi1.9375V0.0625WO6). Bi1.9375Mn0.0625WO6 exhibits ferromagnetic ordering, while Bi1.9375Cu0.0625WO6, Bi1.9375Fe0.0625WO6, Bi1.9375Ni0.0625WO6, and Bi1.9375V0.0625WO6 exhibit Ferrimagnetic ordering. Compared to other element-doped Bi2WO6, Bi1.9375Mn0.0625WO6 shows a larger energy difference between the FM and NM ordering states(ΔE = 18.510 eV), demonstrating stronger magnetic ordering than Cu-, Fe-, Ni-, and V-doped Bi2WO6，and these materials hold potential for application in electronic spin-polarized devices.
Algebraic language for the efficient representation and optimization of quantum circuits
Authors: Escanez-Exposito Daniel , Caballero-Gil Pino , Rodriguez-Vega Marcos , Costa-Cano Francisco , Sáenz-de-Cabezón Eduardo
Published: December 2024

The use of graphical language in quantum computing for the representation of algorithms, although intuitive, is not very useful for different tasks such as the description of quantum circuits in text environments, the calculation of quantum states or the optimization of quantum circuits. While classical circuits can be represented either by circuit graphs or by Boolean expressions, quantum circuits have until now predominantly been illustrated as circuit graphs because no formal language for quantum circuits that allows algebraic manipulations has so far been accepted. This work proposes a means to represent quantum circuits in a convenient and concise manner, similar to the way Boolean expressions are used in classical circuits. The proposed notation allows the consistent and parameterized description of quantum algorithms, as well as the easy handling of the elements that compose it to achieve powerful optimizations in the number of gates of the circuits. To visualize it, a software implementation of an algebraic quantum circuit framework has been made, which allows describing quantum circuits, as well as their respective state vectors, using the proposed algebraic language.
Erbium doped P2O5-BiF3-MgO-ZnO-KF glasses for green laser applications
Authors: Jamalaiah B C , Rao K Venkata , Sagar S Vidya , Balanarayana C , Srihari N V , Khan P Shahab
Published: December 2024

A series of oxyfluorophosphate glasses with the composition (60-x) P2O5 + 10 BiF3 +10 MgO + 10 ZnO + 10 KF + xEr2O3 (0 ≤ x ≥ 2.0 mol%) were prepared using conventional melt quenching method. The amorphous phase of studied glass samples was examined through powder x-ray diffraction. The optical properties were determined using UV–vis-NIR absorption, photoluminescence excitation and emission spectra. The radiative properties were determined using Judd–Ofelt and Fuchtbauer-Ladenburg theories. The optimal Er3+ doping concentration for efficient emission was determined by analysing the emission spectra under 377 nm excitation. The emission spectra of studied glasses exhibited characteristic emission bands of Er3+ ions corresponding to the 2H11/2 → 4I15/2 (529 nm), 4S3/2 → 4I15/2 (545 nm) and 4F9/2 → 4I15/2 (684 nm) transitions. At higher Er3+ doping levels, the emission bands shift towards longer wavelengths showing a red shift. Upon 980 nm excitation for upconversion, the Er3+ ions emitted intense green luminescence through the 4S3/2 → 4I15/2 (545 nm) transition. The applicability of studied glasses for the fabrication of green laser sources was discussed. The glass system containing 0.5 mol% of Er3+ ions was identified to be the optimal choice for designing green laser sources.
Static voltage bilayer optimization for distribution networks based on Sobol’ method
Authors: Liu Zifa , Huai Heyang , Yao Yusen
Published: December 2024

In active distribution networks, the uncertainty of a large number of distributed power sources makes the voltage stability problem of distribution networks more and more prominent. The existing optimization methods tend to deal with the economy and voltage stability of distribution networks as independent objectives, with less consideration of their connection, making it difficult to realize the efficient use of flexible resources. The paper introduces upper and lower connection factors and proposes a two-layer optimization model for distribution network voltage using the Sobol’ method. First, taking into account the uncertainty of distributed power sources and loads in active distribution networks, a probabilistic tidal current calculation model for active distribution networks is constructed, based on which the impact of load fluctuations on the L index is quantitatively analyzed by the global sensitivity of the Sobol’ method. Secondly, the upper and lower connection factors are calculated based on the sensitivity analysis results. The upper economic objective and the lower stability objective are connected through the connection factors to establish a two-layer optimization model to solve the flexible resources in the system optimally. Finally, simulations on the modified IEEE33 node system validate that the proposed optimization model enhances distribution network security while considering economic factors.
Electrochemical immunoassay for gastric cancer biomarker pepsinogen I detection based on PdAgPt/MoS2
Authors: He Chunsheng , Qiu Zhisong , Jin Feng , Weng Lifang , Chen Libin , Wang Lijuan , Jiang Sicong , Shi Jin
Published: December 2024

This study presents a novel electrochemical immunosensor for the detection of pepsinogen I, a potential biomarker for gastric cancer, based on a unique PdAgPt/MoS2 nanocomposite. The key innovation lies in the synergistic combination of trimetallic PdAgPt nanoparticles with MoS2 nanoflowers, which has not been previously reported for pepsinogen I detection. This hybrid material demonstrates exceptional electron transfer properties and a significantly larger electroactive surface area compared to conventional materials. The optimized immunosensor exhibits superior performance metrics: a wide linear range of 0.5–200 ng ml−1 and an unprecedented low detection limit of 0.173 ng ml−1, surpassing existing detection methods. The sensor shows remarkable selectivity with interfering substances exhibiting relative responses below 5%, excellent reproducibility (RSD 3.8%), and outstanding stability (95.6% retention after 30 d). Analysis of spiked serum samples resulted in recoveries ranging from 96.8% to 104.5%, demonstrating the sensor’s practical applicability for early gastric cancer screening. This work represents a significant advancement in developing rapid, sensitive, and cost-effective diagnostic tools for gastric cancer surveillance.
Expert views on carbon pricing in the developing world*
Authors: Lerner Michael , Genovese Federica , Gard-Murray Alexander , Biedenkopf Katja , Kyriakopoulou Danae , Olarte-Peña Andrés , Okullo Samuel J , Castro Marcos , Gadde Harikumar
Published: December 2024

Dozens of governments across the developing world have adopted or are actively considering a variety of carbon pricing policies, but why policymakers prefer some policy designs over others remains uncertain. We argue that expert assessments of carbon pricing primarily center on economic efficiency and distributional concerns, which in turn influence perceptions of technical efficacy and political feasibility. Leveraging a unique conjoint experiment with carbon pricing experts in developing countries, we examine how aspects of policy design influence effectiveness and feasibility, as well as how experts weigh these factors against each other. Design choices that alter the costs and benefits of carbon pricing affect perceptions of the policy’s effectiveness and feasibility, often in opposing directions. Experts are split over which goal is more important overall, preferring political feasibility when distributing costs but weighing effectiveness and feasibility similarly when distributing benefits. Our findings highlight the challenge of balancing the ambition and political risk of pricing carbon in a developing country context.
Signature investigation of misaligned jet in Pelton turbines due to flow obstruction in nozzle
Authors: Chitrakar Sailesh , Prasad Neopane Hari
Published: December 2024

This paper presents a part of the research works related to early stage fault detection and diagnosis of hydraulic turbines. The research works are currently focused on creating a database of the distinctive signals of the faults in the turbine through CFD investigations. The faults in the turbine are induced based on experience and literature review of the common sediment erosion patterns. In the case of Pelton turbines, erosion in the needle with ripple and groove shapes and wavy scales on the buckets are found to be the most common erosion patterns. This paper focuses on asymmetrical erosion patterns of buckets and the needle caused due to flow obstruction in nozzle and consequent misalignment of the jet. The partial blockage for CFD is modelled as a sector of an annulus distributed around the needle. Velocity, pressure, output torque and erosion rates on the needle and buckets are studied. By integrating the trend analysis with machine learning techniques, a real-time condition monitoring tool and procedure can be developed. Since a predictive maintenance of the turbines can be implemented, the outcomes of these research works can have a commercial value for sediment affected power plants globally.
Broad spectrum quality assessment of flow simulations in Pelton turbine runners
Authors: Andolfatto L , Rentschler M , Gervais N
Published: December 2024

The presented work lists quantities of interest that are expected from Computer Fluid Dynamics (CFD) simulations over the course of a Pelton runner design. It covers a broad spectrum of heterogeneous quantities, from simple scalar values such as hydraulic efficiency of the runner to time-dependent multi-dimensional data such as the evolution of the water distribution at the outlet of the runner over a jet passing cycle.

A method is proposed to perform comparison between simulation results and a set of reference experimental results. The approaches selected to quantify agreement between experimental data and simulation results are explained. Finally, the result of the presented work offers a tool evaluating key performance indicators to quantify the discrepancy between simulation results and actual physical behaviour of the turbine. It aims at helping users of numerical simulations to select the most appropriate simulation configuration either for a given application addressing a limited amount of quantities of interest or when they are interested in the best compromise to predict several characteristics of the flow in a Pelton turbine.
Numerical study of nozzle erosion and its cascading impact on jet quality
Authors: Pandey Arun , Shrestha Sajan , Niroula Sagar , Chitrakar Sailesh , Prasad Neopane Hari , Gunnar Dahlhaug Ole
Published: December 2024

Sediment erosion is one of the major factors affecting the overall efficiency of hydro-turbines working under sediment laden conditions. The erosion not only decreases the efficiency but also changes the flow characteristics. However, the research regarding the changes in flow characteristics due to erosion is limited. The objective of this study is to identify the changes in flow characteristics of a Pelton nozzle due to erosion. Particularly, in a Pelton turbine system, the nozzle and the bucket are the components that are mostly affected by the erosion. The flow in the nozzle is unaffected by the erosion in the bucket. Nonetheless, the overall flow characteristics in the bucket can be affected by nozzle erosion. The erosion in the nozzle decreases the jet velocity and make it bit more dispersed which eventually decreases its impact force on the bucket and eventually leads to the decrement in overall efficiency of the turbine. A numerical study was conducted to compare the pressure loss, jet diameter, velocity, and dispersion angle between eroded and uneroded nozzle. Some wavy perturbations were induced on the needle and nozzle casing of the reference uneroded case to create the eroded nozzle case. The CFD simulation was then performed in OpenFOAM using its inbuilt multiphase solver, incompressibleVoF (interFoam). It was observed that, with erosion the total pressure loss, jet diameter, and dispersion angle increases but the velocity of the flow decreases. If these changes in flow get detected during operation, it can be used to develop real-time condition monitoring system.