bluuebunny/crossref_metadata_2025 huggingface dataset:
Reactive oxygen species driven prodrug-based nanoscale carriers for transformative therapies
Authors: Vasvani Shyam , Vasukutty Arathy , Bardhan Rizia , Park In-Kyu , Uthaman Saji
Published: July 2024

Reactive oxygen species (ROS) play a dual role in pathology and therapy. ROS-responsive nanoscale drug carriers offer a promising strategy to leverage elevated ROS levels in diseased tissues for targeted, enhanced therapeutic delivery and efficacy.
OM-Diff: inverse-design of organometallic catalysts with guided equivariant denoising diffusion
Authors: Cornet François , Benediktsson Bardi , Hastrup Bjarke , Schmidt Mikkel N. , Bhowmik Arghya
Published: July 2024

This work presents OM-Diff, an inverse-design framework based on a diffusion generative model for in silico design of organometallic complexes.
Step-scheme CsPbBr3/BiOBr photocatalyst with oxygen vacancies for efficient CO2 photoreduction
Authors: Sun Wanjun , Liu Jifei , Ran Feitian , Li Na , Li Zengpeng , Li Yuanyuan , Wang Kai
Published: July 2024

A novel S-scheme CsPbBr3/BiOBr photocatalyst with oxygen vacancies was fabricated for efficient photocatalytic CO2 reduction, as evidenced by various experimental results and DFT calculations.
Dinuclear enantiopure Ln3+ complexes with (S-) and (R-) 2-phenylbutyrate ligands. Luminescence, CPL and magnetic properties
Authors: Tubau Ànnia , Zinna Francesco , Di Bari Lorenzo , Font-Bardía Mercè , Vicente Ramon
Published: July 2024

Eighteen chiral compounds derivated from the (R)-(−) or (S)-(+)-2-phenylbutyric acid with formula [Ln2(μ-R/S-2-PhBut)4(R/S-2PhBut)2(Bphen)2] are presented. Magnetic and luminescence studies, including CPL spectra of the new complexes, are reported.
Dual role of arsenite in hydrolysis and post-hydrolysis fluorescence sensing of selective pH-dependent probes
Authors: Singh Pushpendra , Sadhu Kalyan K.
Published: July 2024

Arsenite not only selectively hydrolyses the imine-based probe 1, but also shows selective emission with the aldehyde generated from the hydrolysis reaction. The reactivity is compared with other six probes to correlate the pKa of these probes.
Nanoarchitectonics with W18O49 nanobelts and B-doped g-C3N4 nanosheets towards NO and 4-nitrophenol conversion
Authors: Zhang Xiao , Xia Xiang , Yang Ping
Published: July 2024

Construction of heterostructures has been an effective approach for suppressing recombination of photogenerated charge carriers of graphitic carbon nitride (g-C3N4) materials and facilitating solar energy harvesting.
Revolutionizing ORR catalyst design through computational methodologies and materials informatics
Authors: Lucchetti Lanna E. B. , de Almeida James M. , Siahrostami Samira
Published: July 2024

The combination of density functional theory (DFT), machine learning, descriptor-based analysis, and computational hydrogen electrode is pivotal in discovering novel classed of active catalysts for oxygen reduction reaction (ORR).
Association between pre- and post-diagnosis healthy eating index 2020 and ovarian cancer survival: evidence from a prospective cohort study
Authors: Liu Jia-Cheng , Liu Fang-Hua , Zhang De-Yu , Wang Xiao-Ying , Wu Lang , Li Yi-Zi , Xu He-Li , Wei Yi-Fan , Huang Dong-Hui , Li Xiao-Ying , Xiao Qian , Xie Meng-Meng , Liu Pei-Chen , Gao Song , Liu Chuan , Liu Ning , Gong Ting-Ting , Wu Qi-Jun
Published: July 2024

Adherence to the healthy eating index-2020 before and after diagnosis is associated with better overall survival in patients with ovarian cancer.
Assessing the potential of non-pyrophoric Zn(DMP)2 for the fast deposition of ZnO functional coatings by spatial atomic layer deposition
Authors: Johnston Liam , Obenlüneschloß Jorit , Khan Niazi Muhammad Farooq , Weber Matthieu , Lausecker Clément , Rapenne Laetitia , Roussel Hervé , Sanchez-Velazquez Camilo , Bellet Daniel , Devi Anjana , Muñoz-Rojas David
Published: July 2024

Growth rates, environmental impact, and functionality of Zn(DMP)2 are explored for the spatial ALD of ZnO and compared to DEZ.
An evaluation of recent advancements in biological sensory organ-inspired neuromorphically tuned biomimetic devices
Authors: Sinha Animesh , Lee Jihun , Kim Junho , So Hongyun
Published: July 2024

This review unveils advancements in neuroscience, enabling a comprehensive exploration of the capabilities and practical applications of neuromorphic science.
A PEDOT based graft copolymer with enhanced electronic stability
Authors: Gu Modi , Travaglini Lorenzo , Ta Daniel , Hopkins Jonathan , Lauto Antonio , Wagner Pawel , Wagner Klaudia , Officer David L. , Mawad Damia
Published: July 2024

A sulfonated poly(ethylenedioxythiophene) graft copolymer is developed, having exceptional operational and structural stability as an active material in organic electrochemical transistors, despite its high swelling ratio in aqueous electrolyte.
Improving MPI and hyperthermia performance of superparamagnetic iron oxide nanoparticles through fractional factorial design of experiments
Authors: Li Yanchen , Zhang Rui , Barmin Roman , Rama Elena , Schoenen Max , Schrank Franziska , Schulz Volkmar , Slabu Ioana , Kiessling Fabian , Lammers Twan , Pallares Roger M.
Published: July 2024

We utilized a fractional factorial design of experiments to characterize the key factors influencing SPION growth and performance in MPI and magnetic hyperthermia.
Impact of morphology and oxygen vacancy content in Ni, Fe co-doped ceria for efficient electrocatalyst based water splitting
Authors: Mishra Abhaya Kumar , Willoughby Joshua , Estes Shanna L. , Kohler Keliann Cleary , Brinkman Kyle S.
Published: July 2024

Schematic presentation of Ni + Fe co-doped CeO2 mesoporous.
Magnetic clusters as efficient EY-like spin-scattering centres in graphene
Authors: Keijers Wout , Murugesan Ramasamy , Libeert Guillaume , Raes Bart , Brems Steven , De Gendt Stefan , Houssa Michel , Janssens Ewald , Van de Vondel Joris
Published: July 2024

Exploring the ability of atomically precise magnetic Ni4 scatterers to augment graphene's spin activity.
Macauba oil carried by polymeric micelles reduces migration and proliferation of triple-negative breast cancer cells
Authors: Aleixo Davi T. , Gualberto Ana C. M. , Valle Ana B. C. dos S. , da Silva Luan C. , Ferreira Kézia C. B. , Lemos Ari S. de O. , Fabri Rodrigo L. , Tavares Guilherme D. , Cazarim Maurílio de S. , Gameiro Jacy , Pittella Frederico
Published: July 2024

Macauba oil-loaded polymeric micelles exhibit antimigratory, antiproliferative, and cytotoxic activities in triple-negative breast cancer cells, suggesting potential as a therapeutic agent for this aggressive cancer type.
Correction: Mechanical force-driven multi-state memory in WO3−δ thin films
Authors: Yang Mingdi , Lv Zonglin , Li Shan , Li Jiaqi , Cao Jinpeng , Chen Junjie , Wang Yilin , Lin Kun , Li Qiang , Miao Jun , Xing Xianran
Published: July 2024

Correction for ‘Mechanical force-driven multi-state memory in WO3−δ thin films’ by Mingdi Yang et al., Inorg. Chem. Front., 2024, 11, 3919–3926, https://doi.org/10.1039/D4QI00789A.
Ferrocene-based conjugated macrocycles: shotgun synthesis, size-dependent properties and tunable fluorescence intensity
Authors: Zhu Lingyun , Xu Jingdong , Lan Bin , Chen Xinyu , Kono Hideya , Xu Hui , Yan Jianfeng , Li Wenjuan , Yagi Akiko , Yuan Yaofeng , Itami Kenichiro , Li Yuanming
Published: July 2024

Ferrocene-based conjugated macrocycles were efficiently synthesized by a “shotgun” approach. The fluorescence intensity of the macrocycles can be modulated in two intriguing ways: enhancement by adding an oxidant and quenching by adding fullerenes.
The effects of oxygen flow ratio on the properties of AgxO thin films grown by radio frequency magnetron sputtering
Authors: Liu Xiaojiao , Yasuoka Tatsuya , Dang Giang T. , Liu Li , Kawaharamura Toshiyuki
Published: July 2024

When silver oxide was deposited using sputtering, its color changed depending on the oxygen supplied amount. How would the oxygen flow ratio affect the properties of AgxO thin films prepared by radio frequency magnetron sputtering?
Continuous-inline extraction of polar co-solvent during sequential flow reactions
Authors: Kobayashi Kwihwan , Matsuzawa Jun , Kawanami Hajime , Koumura Nagatoshi
Published: July 2024

We developed a sequential flow reaction method for aldol condensation and 1,4-conjugate addition using column reactors packed with solid base catalysts.
A nitroreductase-sensitive near-IR fluorescent biosensor for detecting tumor hypoxia in vivo
Authors: Nisar Safiya , Sui Binglin
Published: July 2024

The near-IR fluorescent biosensor is highly selective and sensitive in responding to the hypoxic microenvironment of tumors, demonstrating high efficiency in detecting tumor hypoxia and the capability of distinguishing tumors of different sizes.
Nature-inspired recycling of a protein mixture into a green fluorescent protein-based hydrogel
Authors: Roset Julià Laura , Maerkl Sebastian J. , Stellacci Francesco
Published: July 2024

Protein metabolism is a wonderful example of polymer recycling. A random mixture of proteins gets digested into amino acids, which then can be used by cells to produce whichever protein is needed at the time of synthesis.
Robust nanoporous NiMn oxide electrocatalysts for the oxygen evolution reaction through defect engineering
Authors: Thomas Arpit , Kumar Ambrish , Sharma Ram K. , Buck Edgar C. , Gwalani Bharat , Bhogra Meha , Arora Harpreet Singh
Published: July 2024

Excellent catalytic performance of oxygen vacancy enriched, nano-porous Mn3O4/Ni/NiMnO3 architecture.
Achieving safe high-voltage lithium-metal batteries by tailoring electrolyte systems
Authors: Lan Kai , Cheng Jancong , Yang XinXin , Fan Jingmin , Zheng Mingseng , Yuan Ruming , Dong Quanfeng
Published: July 2024

A weakly solvating non-flammable electrolyte system enables a safe high-voltage lithium battery by simultaneously facilitating the decomposition of anions and FEC at the electrode surface.
Urea–nonstoichiometric co-modulated LaMnO3 for ultra-high gaseous Hg0 uptake across a broad temperature range
Authors: Hao Runlong , Qian Zhen , Zuo Xiaomeng , Qin Peng , Yang Xiaojie , Ma Zhao , Yuan Bo
Published: July 2024

2U-La0.8MnO3 was developed with a Hg0 saturated adsorption capacity of 23.86 mg g−1, exceeding those of previously reported metal oxides and exhibiting almost 100% removal efficiency across a wide temperature range (40–250 °C).
An improved and scalable method for the preparation of Sn-doped hexagonal tungsten bronze-type iron fluoride materials as cathodes for sodium-ion batteries
Authors: Guo Longlong , Gao Xiang , Chen Qinjia , Li Haoquan , Ren Jian , Wang Ruiting , Shi Rongrong , Gao Wensheng , Bai Yongxiao
Published: July 2024

H2O2-assisted generation of colorless stable complex ions (FeF63−) for tunable doped iron fluoride material preparation.
Pt single atom alloyed sub-1 nm thick Fe overlayer on supported Cu nanoparticles for methylcyclohexane dehydrogenation
Authors: Oda Akira , Ichihashi Kosei , Yamamoto Yuta , Ohtsu Takeshi , Shi Wei , Sawabe Kyoichi , Satsuma Atsushi
Published: July 2024

We successfully developed a Pt single atom alloyed sub-1 nm thick Fe overlayer on Cu nanoparticles capable of catalyzing MCH dehydrogenation with the H2-evolution rate per Pt mass at least 133 times higher than that of state-of-the-art catalysts.
In situ generated α-Co(OH)2/Co3Mo derived from Co–Mo–N for enhanced electrochemical hydrogen evolution reaction
Authors: Zhou Pengfei , Liu Xuncheng , Ge Xiang , Feng Jinxian
Published: July 2024

The CoMoN materials using the conventional hydrothermal method and nitridation treatment. N promotes the formation of α-Co(OH)2 and the HER activity of CoMoN increases initially and then basically remains unchanged with increasing N content.
Ion-sensitive field effect transistor biosensors for biomarker detection: current progress and challenges
Authors: Zou Jie , Bai Hao , Zhang Limei , Shen Yan , Yang Chengli , Zhuang Weihua , Hu Jie , Yao Yongchao , Hu Wenchuang (Walter)
Published: July 2024

The ISFET is a label-free, miniaturized, sensitive, and rapid-response sensor for disease screening and monitoring. This review covers its structure, recent researches, challenges, solutions, and future prospects for biomarker measurement.
Reciprocating thermal behaviour in a series of 7-coordinate Mn(ii) and Co(ii) complexes
Authors: Zhang Le-Shan , Jin Xin-Xin , Wang Li-Xin , Liu Lu-Lu , Qi Rui-Yue , Zhang Xu , Wang Bing-Wu , Xiang Jing , Liu Ji-Yan , Gao Song
Published: July 2024

Four 7-coordinate Mn(ii) and Co(ii) complexes have been obtained. All the compounds exhibit not only slow magnetic relaxation behaviour under an external magnet field, but also reciprocating thermal behaviour at low temperature.
The fast transient AT 2023clx in the nearby LINER galaxy NGC 3799 as a tidal disruption of a very low-mass star
Authors: Charalampopoulos P. , Kotak R. , Wevers T. , Leloudas G. , Kravtsov T. , Pursiainen M. , Ramsden P. , Reynolds T. M. , Aamer A. , Anderson J. P. , Arcavi I. , Cai Y.-Z. , Chen T.-W. , Dennefeld M. , Galbany L. , Gromadzki M. , Gutiérrez C. P. , Ihanec N. , Kangas T. , Kankare E. , Kool E. , Lawrence A. , Lundqvist P. , Makrygianni L. , Mattila S. , Müller-Bravo T. E. , Nicholl M. , Onori F. , Sahu A. , Smartt S. J. , Sollerman J. , Wang Y. , Young D. R.
Published: July 2024

We present an extensive analysis of the optical and ultraviolet (UV) properties of AT 2023clx, the closest optical/UV tidal disruption event (TDE) to date (z = 0.01107), which occurred in the nucleus of the interacting low-ionization nuclear emission-line region (LINER) galaxy, NGC 3799. After correcting for the host reddening (E(B − V)h = 0.179 mag), we find its peak absolute g-band magnitude to be −18.03 ± 0.07 mag, and its peak bolometric luminosity to be Lpk = (1.57 ± 0.19)×1043 erg s−1. AT 2023clx displays several distinctive features: first, it rose to peak within 10.4 ± 2.5 days, making it the fastest rising TDE to date. Our SMBH mass estimate of M̄BH ≈ 106.0 M⊙ –estimated using several standard methods– rules out the possibility of an intermediate-mass BH as the reason for the fast rise. Dense spectral follow-up reveals a blue continuum that cools slowly and broad Balmer and He II lines as well as weak He Iλλ5876,6678 emission features that are typically seen in TDEs. The early, broad (width ∼15 000 km s−1) profile of Hα matches theoretical expectations from an optically thick outflow. A flat Balmer decrement (LHα/LHβ ∼ 1.58) suggests that the lines are collisionally excited rather than being produced via photoionisation, in contrast to typical active galactic nuclei. A second distinctive feature, seen for the first time in TDE spectra, is a sharp, narrow emission peak at a rest wavelength of ∼6353 Å. This feature is clearly visible up to 10 d post-peak; we attribute it to clumpy material preceding the bulk outflow, which manifests as a high-velocity component of Hα (−9584 km s−1). Its third distinctive feature is the rapid cooling during the first ∼20 days after peak, reflected as a break in the temperature evolution. Combining these findings, we propose a scenario for AT 2023clx involving the disruption of a very low-mass star (≲0.1 M⊙) with an outflow launched in our line of sight and with disruption properties that led to efficient circularisation and prompt accretion disc formation, observed through a low-density photosphere.
Globular cluster orbital decay in dwarf galaxies with MOND and CDM: Impact of supernova feedback
Authors: Bílek Michal , Combes Françoise , Nagesh Srikanth T. , Hilker Michael
Published: July 2024

Dynamical friction works very differently for Newtonian gravity with dark matter and in modified Newtonian dynamics (MOND). While the absence of dark matter considerably reduces the friction in major galaxy mergers, analytic calculations indicate the opposite for very small perturbations, such as globular clusters (GCs) sinking in dwarf galaxies. Here, we study the decay of GCs in isolated gas-rich dwarf galaxies using simulations with the Phantom of Ramses code, which enables both the Newtonian and the QUMOND MOND gravity. We modeled the GCs as point masses, and we simulated the full hydrodynamics, with star formation and supernovae feedback. We explored whether the fluctuations in gravitational potential caused by the supernovae can prevent GCs from sinking toward the nucleus. For GCs of typical mass or lighter, we find that this indeed works in both Newtonian and MOND simulations. The GC can even make a random walk. However, we find that supernovae cannot prevent massive GCs (M ≥ 4 × 105 M⊙) from sinking in MOND. The resulting object looks similar to a galaxy with an offset core, which embeds the sunk GC. The problem is much milder in the Newtonian simulations. This result thus favors Newtonian over QUMOND gravity, but we note that it relies on the correctness of the difficult modeling of baryonic feedback. We propose that the fluctuations in the gravitational potential could be responsible for the thickness of the stellar disks of dwarf galaxies and that strong supernova winds in modified gravity can transform dwarf galaxies into ultra-diffuse galaxies.
Element abundances of galactic RGB stars in the APO-K2 catalogue
Authors: Valle G. , Dell’Omodarme M. , Prada Moroni P. G. , Degl’Innocenti S.
Published: July 2024

Aims. We conducted an investigation on the chemical abundances of 4316 stars in the red giant branch (RGB) phase from the recently released APO-K2 catalogue. Our aim was to characterize the abundance trends of the single elements with [α/Fe], mainly focusing on C, N, and O, which are the most relevant for the estimation of stellar ages.

Methods. The chemical analysis of the RGB sample involved cross-matching data from the APO-K2 catalogue with individual element abundances from APOGEE DR17.

Results. The analysis detected a statistically significant difference in the [(C+N+O)/Fe]–[α/Fe] trend with respect to the simple α-enhancement scenario. This difference remained robust across different choices for the reference solar mixture and potential zero-point calibrations of C and N abundances. The primary discrepancy was a steeper increase in [O/Fe] with [α/Fe], reaching a 0.1 dex difference at [α/Fe] = 0.3. Notably, the impact on the evolutionary timescale of such oxygen over-abundance with respect to the commonly adopted uniform α-enhancement is rather limited. We verified that stellar models computed using an ad hoc O-rich mixture sped up the evolution by only 1% at [α/Fe] = 0.3, due to the counterbalancing effects of O enrichment on both the evolutionary timescale and the Z-to-[Fe/H] relationship.
Planck data revisited: Low-noise synchrotron polarization maps from the WMAP and Planck space missions
Authors: Delabrouille Jacques
Published: July 2024

Context. Observations of cosmic microwave background (CMB) polarization, essential for probing a potential phase of inflation in the early Universe, suffer from contamination by polarized emission from the Galactic interstellar medium.

Aims. This work combines existing observations from the WMAP and Planck space missions to make a low-noise map of polarized synchrotron emission that can be used to clean forthcoming CMB observations.

Methods. We combine DR5 K, Ka and Q WMAP maps with PR4 30 and 44 GHz Planck LFI maps, using weights that near-optimally combine the observations as a function of sky direction, angular scale, and polarization orientation.

Results. We publish well-characterized maps of synchrotron Q and U Stokes parameters at ν = 30 GHz and an angular resolution of 1 degree. A statistical description of uncertainties is provided with Monte-Carlo simulations of additive and multiplicative errors.

Conclusions. Our maps are the most sensitive full-sky maps of synchrotron polarization to date, and are made available to the scientific community on a dedicated website.
The MeerKAT Fornax Survey
Authors: Serra P. , Oosterloo T. A. , Kamphuis P. , Józsa G. I. G. , de Blok W. J. G. , Bryan G. L. , van Gorkom J. H. , Iodice E. , Kleiner D. , Loni A. , Loubser S. I. , Maccagni F. M. , Molnár D. , Peletier R. , Pisano D. J. , Ramatsoku M. , Smith M. W. L. , Verheijen M. A. W. , Zabel N.
Published: July 2024

We present MeerKAT Fornax Survey H I observations of NGC 1427A, a blue irregular galaxy with a stellar mass of ∼2 × 109 M⊙ located near the centre of the Fornax galaxy cluster. Thanks to the excellent resolution (1–6 kpc spatially, 1.4 km s−1 in velocity) and H I column density sensitivity (∼4 × 1019 to ∼1018 cm−2 depending on resolution), our data deliver new insights on the long-debated interaction of this galaxy with the cluster environment. We confirm the presence of a broad, one-sided, starless H I tail stretching from the outer regions of the stellar body and pointing away from the cluster centre. We find the tail to have 50% more H I (4 × 108 M⊙) and to be 3 times longer (70 kpc) than in previous observations. In fact, we detect scattered H I clouds out to 300 kpc from the galaxy in the direction of the tail – possibly the most ancient remnant of the passage of NGC 1427A through the intracluster medium of Fornax. Both the velocity gradient along the H I tail and the peculiar kinematics of H I in the outer region of the stellar body are consistent with the effect of ram pressure given the line-of-sight motion of the galaxy within the cluster. However, several properties cannot be explained solely by ram pressure and suggest an ongoing tidal interaction. This includes: the close match between dense H I and stars within the disturbed stellar body; the abundant kinematically anomalous H I; and the inversion of the H I velocity gradient near the base of the H I tail. We rule out an interaction with the cluster tidal field, and conclude that NGC 1427A is the result of a high-speed galaxy encounter or of a merger started at least 300 Myr ago, where ram pressure shapes the distribution and kinematics of the H I in the perturbed outer stellar body and in the tidal tails.
Long gamma-ray burst light curves as the result of a common stochastic pulse–avalanche process
Authors: Bazzanini L. , Ferro L. , Guidorzi C. , Angora G. , Amati L. , Brescia M. , Bulla M. , Frontera F. , Maccary R. , Maistrello M. , Rosati P. , Tsvetkova A.
Published: July 2024

Context. The complexity and variety exhibited by the light curves of long gamma-ray bursts (GRBs) enclose a wealth of information that has not yet been fully deciphered. Despite the tremendous advance in the knowledge of the energetics, structure, and composition of the relativistic jet that results from the core collapse of the progenitor star, the nature of the inner engine, how it powers the relativistic outflow, and the dissipation mechanisms remain open issues.

Aims. A promising way to gain insights is describing GRB light curves as the result of a common stochastic process. In the Burst And Transient Source Experiment (BATSE) era, a stochastic pulse avalanche model was proposed and tested through the comparison of ensemble-average properties of simulated and real light curves. Here our aim was to revive and further test this model.

Methods. We applied it to two independent datasets, BATSE and Swift/BAT, through a machine learning approach: the model parameters are optimised using a genetic algorithm.

Results. The average properties were successfully reproduced. Notwithstanding the different populations and passbands of both datasets, the corresponding optimal parameters are interestingly similar. In particular, for both sets the dynamics appear to be close to a critical state, which is key to reproducing the observed variety of time profiles.

Conclusions. Our results propel the avalanche character in a critical regime as a key trait of the energy release in GRB engines, which underpins some kind of instability.
Fast X-ray/IR observations of the black hole transient Swift J1753.5–0127: From an IR lead to a very long jet lag
Authors: Ulgiati A. , Vincentelli F. M. , Casella P. , Veledina A. , Maccarone T. J. , Russell D. M. , Uttley P. , Ambrosino F. , Baglio M. C. , Imbrogno M. , Melandri A. , Motta S. E. , O’Brien K. , Sanna A. , Shahbaz T. , Altamirano D. , Fender R. P. , Maitra D. , Malzac J.
Published: July 2024

We report two epochs of simultaneous near-infrared (IR) and X-ray observations of the low-mass X-ray binary black hole candidate Swift J1753.5–0127 with a subsecond time resolution during its long 2005–2016 outburst. Data were collected strictly simultaneously with VLT/ISAAC (KS band, 2.2 μm) and RXTE (2–15 keV) or XMM-Newton (0.7–10 keV). A clear correlation between the X-ray and the IR variable emission is found during both epochs but with very different properties. In the first epoch, the near-IR variability leads the X-ray by ∼130 ms, which is the opposite of what is usually observed in similar systems. The correlation is more complex in the second epoch, with both anti-correlation and correlations at negative and positive lags. Frequency-resolved Fourier analysis allows us to identify two main components in the complex structure of the phase lags: the first component, characterised by a near-IR lag of a few seconds at low frequencies, is consistent with a combination of disc reprocessing and a magnetised hot flow; the second component is identified at high frequencies by a near-IR lag of ≈0.7 s. Given the similarities of this second component with the well-known constant optical/near-IR jet lag observed in other black hole transients, we tentatively interpret this feature as a signature of a longer-than-usual jet lag. We discuss the possible implications of measuring such a long jet lag in a radio-quiet black hole transient.
Non-linear torsional Alfvén waves evolving in stratified viscous plasmas: Coronal hole plumes
Authors: Hejazi S. M. , Vasheghani Farahani S. , Hajisharifi K. , Mehdian H.
Published: July 2024

Aims. We model solar atmospheric structures characterised by parallel structuring. We focus on Alfvén waves in the weakly non-linear regime to highlight the efficiency of non-linear wave steepening when dissipative effects are prominent. We also consider the local and equilibrium conditions involved in shock formation and the shock’s contributions to coronal seismology.

Methods. Coronal plumes were modelled analytically by implementing the magnetohydrodynamic (MHD) theory in cylindrical geometry. Here, the stratification and viscosity are present internal to the plume, whilst effects of the external medium, together with equilibrium conditions, are implied where the magnetic fields are parallel to the plume axis. We implemented a second-order thin flux tube approximation to obtain a wave equation that points to effects tied to non-linear, dissipative, and stratification terms, as well as terms representing atmospheric conditions.

Results. The impact of shear viscosity on non-linear Alfvén waves extracted by the Cohen-Kulsrud-Burgers-type equation proves more efficient when propagated to higher altitudes. The dissipative effects linked to the dimensionless viscosity indicate that the dissipative effects are not linear. Meanwhile, the delay in shock formation enables energy conversions at higher altitudes, thereby maintaining coronal heating at higher levels. The efficiency of parallel structuring and viscous damping is enhanced by such transverse structuring, as it is directly proportional to the external plasma-β. It is observed that Alfvén pulses may undergo a backward shock, either in the lower levels of coronal plasma or as they propagate toward higher regions, implying a conversion of energy occurring at various altitudes. A peak was observed, indicating that the interplay reverses at heights around 1.5 solar radii. Such effects are shown to play a key role in the context of coronal seismology.
The 2024 KIDA network for interstellar chemistry
Authors: Wakelam V. , Gratier P. , Loison J.-C. , Hickson K. M. , Penguen J. , Mechineau A.
Published: July 2024

Context. The study of the chemical composition of the interstellar medium (ISM) requires a strong synergy between laboratory astrophysics, modeling, and observations. In particular, astrochemical models have been developed for decades now and include an increasing number of processes studied in the laboratory or theoretically. These models follow the chemistry both in the gas phase and at the surface of interstellar grains. Since 2012, we have provided complete gas-phase chemical networks for astrochemical codes that can be used to model various environments of the ISM.

Aims. Our aim is to introduce the new up-to-date astrochemical network kida.uva.2024 together with the ice chemical network and the fortran code to compute time dependent compositions of the gas, the ice surface, and the ice mantles under physical conditions relevant for the ISM.

Methods. The gas-phase chemical reactions, as well as associated rate coefficients, included in kida.uva.2024 were carefully selected from the KIDA online database and represent the most recent values. The model predictions for cold core conditions and for when considering only gas-phase processes were computed as a function of time and compared to the predictions obtained with the previous version, kida.uva.2014. In addition, key chemical reactions were identified. The model predictions, including both gas and surface processes, were compared to the molecular abundances as observed in the cold core TMC1-CP.

Results. Many gas-phase reactions were revised or added to produce kida.uva.2024. The new model predictions are different by several orders of magnitude for some species. The agreement of this new model with observations in TMC-1 (CP) is, however, similar to the one obtained with the previous network.
Distribution of the number of peaks within a long gamma-ray burst: The full Fermi/GBM catalogue
Authors: Maccary R. , Maistrello M. , Guidorzi C. , Sartori M. , Amati L. , Bazzanini L. , Bulla M. , Camisasca A. E. , Ferro L. , Frontera F. , Tsvetkova A.
Published: July 2024

Context. The dissipation process responsible for the long gamma-ray burst (GRB) prompt emission and the kind of dynamics that drives the release of energy as a function of time are still key open issues. We recently found that the distribution of the number of peaks per GRB is described by a mixture of two exponentials, suggesting the existence of two behaviours that turn up as peak-rich and peak-poor time profiles.

Aims. Our aims are to study the distribution of the number of peaks per GRB of the entire catalogue of about 3000 GRBs observed by the Fermi Gamma-ray Burst Monitor (GBM) and to make a comparison with previous results obtained from other catalogues.

Methods. We identified GRB peaks using the MEPSA code and modelled the resulting distribution following the same procedure that was adopted in the previous analogous investigation.

Results. We confirm that only a mixture of two exponentials can model the distribution satisfactorily, with model parameters that fully agree with those found from previous analyses. In particular, we confirm that (21 ± 4)% of the observed GRBs are peak-rich (8 ± 1 peaks per GRB on average), while the remaining 80% are peak-poor (2.12 ± 0.10 peaks per GRB on average).

Conclusions. We confirm the existence of two different components, peak-poor and peak-rich GRBs, that make up the observed GRB populations. Together with previous analogous results from other GRB catalogues, these results provide compelling evidence that GRB prompt emission is governed by two distinct regimes.
The MAGPI survey: The interdependence of the mass, star formation rate, and metallicity in galaxies at z ∼ 0.3
Authors: Koller M. , Ziegler B. , Ciocan B. I. , Thater S. , Mendel J. T. , Wisnioski E. , Battisti A. J. , Harborne K. E. , Foster C. , Lagos C. , Croom S. M. , Grasha K. , Papaderos P. , Remus R. S. , Sharma G. , Sweet S. M. , Valenzuela L. M. , van de Ven G. , Zafar T.
Published: July 2024

Aims. Star formation rates (SFRs), gas-phase metallicities, and stellar masses are crucial for studying galaxy evolution. The different relations resulting from these properties give insights into the complex interplay of gas inside galaxies and their evolutionary trajectory and current characteristics. We aim to characterize these relations at z ∼ 0.3, corresponding to a 3–4 Gyr lookback time, to gather insight into the galaxies’ redshift evolution.

Methods. We utilized optical integral field spectroscopy data from 65 emission-line galaxies from the MUSE large program MAGPI at a redshift of 0.28 < z < 0.35 (average redshift of z ∼ 0.3) and spanning a total stellar mass range of 8.2 < log(M*/M⊙) < 11.4. We measured emission line fluxes and stellar masses, allowing us to determine spatially resolved SFRs, gas-phase metallicities, and stellar mass surface densities. We derived the resolved star formation main sequence (rSFMS), resolved mass metallicity relation (rMZR), and resolved fundamental metallicity relation (rFMR) at z ∼ 0.3, and compared them to results for the local Universe.

Results. We find a relatively shallow rSFMS slope of ∼0.425 ± 0.014 compared to the expected slope at this redshift for an ordinary least square (OLS) fitting routine. For an orthogonal distance regression (ODR) routine, a much steeper slope of ∼1.162 ± 0.022 is measured. We confirm the existence of an rMZR at z ∼ 0.3 with an average metallicity located ∼0.03 dex above the local Universe’s metallicity. Via partial correlation coefficients, evidence is found that the local metallicity is predominantly determined by the stellar mass surface density and has a weak secondary (inverse) dependence on the SFR surface density ΣSFR. Additionally, a significant dependence of the local metallicity on the total stellar mass M* is found. Furthermore, we find that the stellar mass surface density Σ* and M* have a significant influence in determining the strength with which ΣSFR correlates with the local metallicity. We observe that at lower stellar masses, there is a tighter correlation between ΣSFR and the gas-phase metallicity, resulting in a more pronounced rFMR.
Cloud structure and young star distribution in the Dragonfish complex
Authors: Sanchez Nestor , Nespoli Elisa , Gonzalez Marta , Climent Juan B.
Published: July 2024

Context.Star formation is a complex process involving several physical mechanisms that interact with each other at different spatial scales. One way to shed some light on this process is to analyse the relation between the spatial distributions of gas and newly formed stars. In order to obtain robust results, it is necessary for this comparison to be made using quantitative and consistent descriptors that are applied to the same star-forming region.

Aims.We used fractal analysis to characterise and compare in a self-consistent way the structure of the cloud and the distribution of young stellar objects (YSO) in the Dragonfish star-forming complex.

Methods.Different emission maps of the Dragonfish nebula were retrieved from the NASA/IPAC Infrared Science and thePlanckLegacy archives. Moreover, we used photometric information from the AllWISE catalogue to select a total of 1082 YSOs in the region. We derived the physical properties for some of these from their spectral energy distributions (SEDs). For the cloud images and YSOs, the three-dimensional fractal dimension (Df) was calculated using previously developed and calibrated algorithms.

Results.The fractal dimension of the Dragonfish nebula (Df= 2.6–2.7) agrees very well with values previously obtained for the Orion, Ophiuchus, and Perseus clouds. On the other hand, YSOs exhibit a significantly lower value on average (Df= 1.9–2.0), which indicates that their structure is far more clumpy than the material from which they formed. Younger Class I and Class II sources have lower values (Df= 1.7 ± 0.1) than more evolved transition disk objects (Df= 2.2 ± 0.1), which shows a certain evolutionary effect according to which an initially clumpy structure tends to gradually disappear over time.

Conclusions.The structure of the Dragonfish complex is similar to that of other molecular clouds in the Galaxy. However, we found clear and direct evidence that the clustering degree of the newly born stars is significantly higher than that of the parent cloud from which they formed. The physical mechanism behind this behaviour is still not clear.
Hard X-rays from the deep solar atmosphere
Authors: Chitta L. P. , Hannah I. G. , Fletcher L. , Hudson H. S. , Young P. R. , Krucker S. , Peter H.
Published: July 2024

Explosive transient events occur throughout the solar atmosphere. The differing manifestations range from coronal mass ejections to Ellermann bombs. The former may have negligible signatures in the lower atmosphere, and the latter may have negligible nonthermal emissions such as hard X-radiation. A solar flare generally involves a broad range of emission signatures. Using a suite of four space-borne telescopes, we report a solar event that combines aspects of simple UV bursts and hard X-ray emitting flares at the same time. The event is a compact C-class flare in active region AR11861, SOL2013-10-12T00:30. By fitting a combined isothermal and nonthermal model to the hard X-ray spectrum, we inferred plasma temperatures in excess of 15 MK and a nonthermal power of about 3 × 1027 erg s−1 in this event. Despite these high temperatures and evidence for nonthermal particles, the flare was mostly confined to the chromosphere. However, the event lacked clear signatures of UV spectral lines, such as the Fe XII 1349 Å and Fe XXI 1354 Å emission lines, which are characteristic of emission from hotter plasma with a temperature over 1 MK. Moreover, the event exhibited very limited signatures in the extreme-UV wavelengths. Our study indicates that a UV burst – hard X-ray flare hybrid phenomenon exists in the low solar atmosphere. Plasma that heats to high temperatures coupled with particle acceleration by magnetic energy that is released directly in the lower atmosphere sheds light on the nature of active region core heating and on inferences of flare signatures.
More sulphur in TMC-1: Discovery of the NC3S and HC3S radicals with the QUIJOTE line survey
Authors: Cernicharo J. , Cabezas C. , Agúndez M. , Fuentetaja R. , Tercero B. , Marcelino N. , de Vicente P.
Published: July 2024

We present the detection of the free radicals NC3S and HC3S towards TMC-1 with the QUIJOTE line survey. The derived column densities are (1.4 ± 0.2)×1011 for NC3S and (1.5 ± 0.2)×1011 for HC3S. We searched for NCCS, but only three transitions are within the domain of our QUIJOTE line survey and the observed lines are marginally detected at the 3σ level, providing an upper limit to its column density of ≤6 × 1010 cm−2. We also unsuccessfully searched for longer species of the NCnS (n ≥ 4) and HCnS (n ≥ 5) families in our TMC-1 data. A chemical model based on a reduced set of reactions involving HC3S and NC3S predicts abundances that are 10–100 times below the observed values. These calculations indicate that the most efficient reactions of formation of HC3S and NC3S in the model are S + C3H2 and N + HC3S, respectively, while both radicals are very efficiently destroyed through reactions with neutral atoms.
Evaluation of wear behavior on AISI 431 by vaccum annealing method for sustainable applications
Authors: Kumar P. Ravi , Kannan N. Senthil , Kumar J. Dinesh , Pradeep P. Sai , Iyyappan M. , Arun K.K. , Subbu R.
Published: July 2024

In this research work, the vacuum annealed stainless steel samples were subjected to a constant load. The wear behavior of AISI 431 sample were examined by using pin on disc wear tester. The vacuum annealing were used to preserve the stability between ductility and brittleness. The samples were created in cylindrical shape with a length of 40 mm and diameter 8mm. For this current research, 3 samples are treated at 600°C, 660°C, 820°C temperatures and they were assigned asA1, A2 and A3 respectively. The outcome of vacuum annealing is that to reduce the hardness and increase in ductility, to overcome the material from defects and release internal stress. The hardness, wear behavior were measured for the treated and untreated samples. To evaluate the wear behavior, comparison of results, wear test studies and scanning electronic microscope analysis were done.
Thermoplastic polymer track with gearing mechanism to harvest green energy for sustainable development
Authors: Hameed Siddiqui Sajid , Chandra Nayak Ramesh , Fidvi Huzaifa , Khan N.H. , Vasantrao Kulkarni Mahesh , Ghutke Pratik C. , Roul Manmatha Ku.
Published: July 2024

Consumption of energy and its demand is increasing constantly. There are various ways to generate energy. Non-renewable energy sources are in high demand, which causes harmful effects on the atmosphere. So environmentally friendly energy sources are very much required. Recently various researchers have been working towards green and environment friendly renewable energy causes. Energy generation from renewable sources, India is within top five position throughout the world. Support towards enhancement of energy generation by renewable sources has been declared by our Honourable Prime minister. The present work deals with a designed model to generate electricity by utilizing energy from footstep movement and vehicle motion. The designed model consists of a gearing mechanism, lever, and thermoplastic polymer track attachment. Thermoplastic tracks are easy to use because of their easier attachment and smooth surface. It is required to attach our designed system in places where maximum mobility of people and vehicle motions is possible. Generally, the places are national highways, temple roads, mall areas, etc. Due to movements on the track, the pressure energy of the foot and vehicle wheels transfers to rotational energy through the gearing attachments of our designed system. This rotational energy is utilized to rotate the armature of the generator to generate electricity and that electricity is stored in the battery for utilization on demand. The lever arm and thermoplastic track are placed with a 10 mm gap so that when load is applied on the track, the thermoplastic will deflect and the load will be transferred to the lever. Due to the provision of a gearing mechanism in our designed system, less input on the track will produce the required rotation of the generator shaft. Natural walking on the track to harvest energy without disturbing the body is very suitable for the stability of this designed system due to the provision of thermoplastic tracks.
Identification of weld sub-surface defects by radiographic images using texture features
Authors: Ramana E.V. , Penekalapati Sai Varun , Kumar Namala Kiran
Published: July 2024

Non-Destructive Testing (NDT) is important to detect sub-surface defects in the weldments to ensure the quality of weld joints. The weld radiographs are digitized using a high-resolution digital camera. Data augmentation techniques are applied to expand the radiographic image dataset. Multi-class defect classification is done using the Gray-level co-occurrence matrix as a feature extractor and these features are given as input to various classifiers for classifying slag inclusion, incomplete penetration, and acceptable weld bead classes. The proposed methodology achieved the highest accuracies of 84%,83%,80%,70%, and 64% respectively for GLCM plus Random Forest, GLCM plus XGBoost, GLCM plus lightGBM, GLCM plus KNN, and GLCM plus SVM. The technology of applying ML techniques on radiographic images in detection of defects in welding as well as other manufacturing processes can be a sustainable practice.
Investigation and analysis of a sustainable agro-based nanocoating on surface of metallic materials
Authors: Afolalu Sunday A. , Ikumapayi Omolayo M. , Laseinde Opeyeolu T. , Ogedengbe Temitayo S. , Jen Tien-Chien , Akinlabi Stephen A. , Akinlabi Esther T.
Published: July 2024

In this study, nanotechnology was used to develop a coating from agricultural waste. Banana peels underwent various chemical processes, nanoparticles were developed and tests were conducted to validate it. The metal samples used for coating application were made of mild steel which is used to produce a large percentage of metal parts in the industry and was selected for this research project due to that reason. The metals were cut into 50 mm x 50 mm and 50 mm x 30 mm. The sample coatings included a control coating which was used as the yardstick to know the effects of the nano coating applied which contained various concentrations of nanoparticles showed results that were more favorable than the coatings that were applied without nanoparticles contained in them. Qualitative analysis of the coated metal samples A to G showed that sample E which had 7.24 grams of nanoparticles contained in it had the highest amount of hardness while sample A which was control coating possessed the least hardness amount. The abrasion test of the samples revealed that sample D which had 21.72 grams of nanoparticles contained in it possessed the highest weight of coating before and after the abrasion test
Multi-Variate Analysis of Shell & Tube Heat Exchanger using Principal Component Analysis
Authors: Nargundkar Aniket , Gulia Vikas , Sur Anirban
Published: July 2024

Shell & Tube Heat Exchangers (STHEs) are a critical component for various industrial applications such as chemical, oil & gas, power, etc. Due to their complex design and high manufacturing cost, the efficient operation and optimum design are quite important for overall cost minimization. Multivariate Analysis (MVA) is a technique used for analysing data with more than one type of measurement. In this paper, MVA of STHEs is carried out using Principal Component Analysis (PCA). 12 variables which predicts the Thermo-Hydraulic Performance & the costs for STHEs are considered. In total, 100 data points are generated and analysed. Two Principal Components (PCs) are adopted and scores & loadings plots are plotted. It is concluded that the first principal component primarily measures design and flow characteristics of STHE while the second principal component has negative coefficients for the factors Res, Nt, Ret, L, do, di and At which signifies the inverse relationship between PC2 and these factors. The current work can be extended further with applications of Partial Least Square Regression and various Machine Learning algorithms.
Sustainable synthesis of eucalyptus globulus – titanium-magnesium nano composite ('EuTiMg NC’) for the photocatalytic degradation of methylene blue
Authors: Amrutha Satti , Dinesh Nilikonda , Madhuri Yarlagadda , Naveen Reddy Gade , Rao Poiba Venkata , Vangalapati Meena
Published: July 2024

Synthetic dyes that escape into the environment haphazardly endanger both human health and ecosystems. Because of its toxicity and endurance, methylene blue (MB) stands out amongst these dyes as a significant contaminant. Conventional dye removal techniques can entail expensive and energy-intensive procedures. However, there has been a rise in interest recently in investigating sustainable and environmentally suitable substitutes for dye degradation. Because of their availability, affordability, and innate capacity to interact with contaminants, natural materials like leaves have become increasingly attractive options for restoration of the environment. Eucalyptus Globulus blended with titanium and magnesium nanoparticles to yield a novel environmentally friendly composite, 'EuTiMg'. The degradative capacity of the composite against methylene blue, a prevalent pollutant in water, was assessed by a range of analytical methods, such as SEM, TGA, FTIR, and BET analysis. To increase the composite’s photocatalytic activity, we also used Response Surface Methodology (RSM) to optimize the synthesis process. According to our research, 'EuTiMg' composite exhibits better pollutant degrading efficiency and is environmentally benign, making it a viable sustainable option for water treatment applications.