bluuebunny/crossref_metadata_2025 huggingface dataset:
Dark matter reconstruction from stellar orbits in the Galactic centre
Authors: Lechien T. , Heißel G. , Grover J. , Izzo D.
Published: March 2024

Context. Current constraints on distributed matter in the innermost Galactic centre (such as a cluster of faint stars and stellar remnants, dark matter, or a combination thereof) based on the orbital dynamics of the visible stars closest to the central black hole typically assume simple functional forms for the distributions.

Aims. We aim to take a general model-agnostic approach in which the form of the distribution is not constrained by prior assumptions on the physical composition of the matter. This approach yields unbiased, entirely observation-driven fits for the matter distribution and places constraints on our ability to discriminate between different density profiles (and consequently between physical compositions) of the distributed matter.

Methods. We constructed a spherical shell model with the flexibility to fit a wide variety of physically reasonable density profiles by modelling the distribution as a series of concentric mass shells. We tested this approach in an analysis of mock observations of the star S2.

Results. For a sufficiently large and precise data set, we find that it is possible to discriminate among several physically motivated density profiles. However, for data coming from current and expected next generation observational instruments, the potential for profile distinction will remain limited by the precision of the instruments. Future observations will still be able to constrain the overall enclosed distributed mass within the apocentre of the probing orbit in an unbiased manner. We interpret this in the theoretical context of constraining the secular versus non-secular orbital dynamics.

Conclusions. Our results show that while stellar data over multiple orbits of currently known stars will eventually yield model-agnostic constraints for the overall amount of distributed matter within the probe’s apocentre in the innermost Galactic centre, an unbiased model distinction made by determining the radial density profile of the distribution is, in principle, out of the measurement accuracy of the current and next-generation instruments. Constraints on dark matter models will therefore remain subject to model assumptions and will not be able to significantly downsize the zoo of candidate models.
Long-period modulation of the classical T Tauri star CI Tau
Authors: Manick R. , Sousa A. P. , Bouvier J. , Almenara J. M. , Rebull L. , Bayo A. , Carmona A. , Martioli E. , Venuti L. , Pantolmos G. , Kóspál Á. , Zanni C. , Bonfils X. , Moutou C. , Delfosse X. ,   The SLS Consortium
Published: March 2024

Context. Detecting planets within protoplanetary disks around young stars is essential for understanding planet formation and evolution. However, planet detection using the radial velocity method faces challenges due to the strong stellar activity in these early stages.

Aims. We detect long-term periodicities in photometric and spectroscopic time series of the classical T Tauri star (CTTS) CI Tau, and retrieve evidence for inner embedded planets in its disk.

Methods. The study conducted photometric and spectroscopic analyses using K2 and Las Cumbres Observatory Global Network light curves, and high-resolution spectra from ESPaDOnS and SPIRou. We focused our radial velocity analysis on a wavelength domain less affected by spot activity. To account for spot effects, a quasi-periodic Gaussian process model was applied to K2 light curve, ESPaDOnS, and SPIRou radial velocity data. Additionally, a detailed bisector analysis on cross-correlation functions was carried out to understand the cause of long-term periodicity.

Results. We detect coherent periods at ~6.6d, 9d, ~11.5d, ~14.2d, and ~25.2d, the last of which is seen consistently across all datasets. Bisector analysis of the cross-correlation functions provides strong hints for combined activity-induced and Doppler reflex signals in the radial velocities at a period of 25.2 d. Our analysis suggests that this periodicity is best explained by the presence of a 3.6 ± 0.3 MJup eccentric (e ~ 0.58) planet at a semi-major axis of 0.17 au.

Conclusions. We report the detection of a massive inner planet in CI Tau. Our study outlines the difficulty of searching for disk-embedded planets in the inner 0.1 au of young and active systems. When searching for planets in actively accreting stars such as CI Tau, we demonstrate that the primary limitation is stellar activity rather than the precision of RV measurements provided by the instrument.
Introducing the TNG-Cluster simulation: Overview and the physical properties of the gaseous intracluster medium
Authors: Nelson Dylan , Pillepich Annalisa , Ayromlou Mohammadreza , Lee Wonki , Lehle Katrin , Rohr Eric , Truong Nhut
Published: March 2024

We introduce the new TNG-Cluster project, an addition to the IllustrisTNG suite of cosmological magnetohydrodynamical simulations of galaxy formation. Our objective is to significantly increase the statistical sampling of the most massive and rare objects in the Universe: galaxy clusters with log(M200c/M⊙) ≳ 14.3 − 15.4 at z = 0. To do so, we re-simulate 352 cluster regions drawn from a 1 Gpc volume that is 36 times larger than TNG300, keeping the IllustrisTNG physical model entirely fixed as well as the numerical resolution. This new sample of hundreds of massive galaxy clusters enables studies of the assembly of high-mass ellipticals and their supermassive black holes (SMBHs), brightest cluster galaxies (BCGs), satellite galaxy evolution and environmental processes, jellyfish galaxies, intracluster medium (ICM) properties, cooling and active galactic nuclei (AGN) feedback, mergers and relaxedness, magnetic field amplification, chemical enrichment, and the galaxy-halo connection at the high-mass end, with observables from the optical to radio synchrotron and the Sunyaev-Zeldovich (SZ) effect, to X-ray emission, as well as their cosmological applications. We present an overview of the simulation, the cluster sample, select comparisons to data, and a first look at the diversity and physical properties of our simulated clusters and their hot ICM.
Phase-resolved XMM-Newton observations of the massive post-RLOF system HD 149404
Authors: Rauw G. , Lizin S. , Rosu S. , Mossoux E.
Published: March 2024

Context. We investigated the X-ray emission of HD 149404, a 9.81-day period O-star binary in a post-Roche lobe overflow evolutionary stage. X-ray emission of O-star binaries consists of the intrinsic emission of the individual O stars and a putative additional component arising from the wind-wind interaction.

Aims. Phase-locked variations in the X-ray spectra can be used to probe the properties of the stellar winds of such systems.

Methods. XMM–Newton observations of HD 149404 collected at two conjunction phases and a quadrature phase were analysed. X-ray spectra were extracted and flux variations as a function of orbital phase were inferred. The flux ratios were analysed with models considering various origins for the X-ray emission.

Results. The highest and lowest X-ray fluxes are observed at conjunction phases respectively with the primary and secondary star in front. The flux variations are nearly grey with only marginal energy dependence. None of the models accounting for photoelectric absorption by homogeneous stellar winds perfectly reproduces the observed variations. Whilst the overall X-ray luminosity is consistent with a pure intrinsic emission, the best formal agreement with the observed variations is obtained with a model assuming pure windwind collision X-ray emission.

Conclusions. The lack of significant energy-dependence of the opacity most likely hints at the presence of optically thick clumps in the winds of HD149404.
Examining the detectability of ringing on highly eccentric exoplanets
Authors: Vanrespaille M. , Baeyens R. , Schneider A. , Carone L. , Decin L.
Published: March 2024

Context. Eccentric exoplanets offer an opportunity to study the response of an atmosphere to changing thermal forcing and the robustness of the super-rotating equatorial jet seen on tidally locked hot Jupiters. However, the atmospheric dynamics on eccentric planets strongly depend on the planetary rotation period, which is difficult to constrain observationally. The ringing phenomenon, whereby the observed emission increases and decreases after the periastron passage as the flash-heated hemisphere rotates into and out of view, can provide a tight constraint on rotation.

Aims. We studied five highly eccentric transiting exoplanets HAT-P-2 b, HD 80606 b, TOI-3362 b, TOI-4127 b and HD 17156 b to find which displays strong ringing signals that are sufficiently strong for the James Webb Space Telescope (JWST) to detect.

Methods. We implemented the treatment of eccentricity and non-synchronous rotation in the non-grey climate model expeRT/MITgcm and generated synthetic light curves.

Results. We find four detectable ringing peaks on HD 80606 b and some undetectable ringing on TOI-4127 b and HD 17156 b. The lack of clouds, photo-chemistry and obliquity in our models may have led us to overestimate the amplitude of the ringing however. The strength of the ringing signal is mostly determined by the eccentricity, planetary rotation period, planet-to-star radius ratio and apparent magnitude of the system. We searched for more exoplanets that could show ringing but found no candidates as promising as HD 80606 b.

Conclusions. We recommend prioritising HD 80606 b as a target for ringing with JWST. A baseline of five days after the periastron passage would capture three ringing peaks, which is sufficient to tightly constrain the planetary rotation period. An extension to seven days would add a fourth peak, which would allow us to verify the rotation period.
Is GN-z11 powered by a super-Eddington massive black hole?
Authors: Bhatt Maulik , Gallerani Simona , Ferrara Andrea , Mazzucchelli Chiara , D’Odorico Valentina , Valentini Milena , Zana Tommaso , Farina Emanuele Paolo , Chakraborty Srija
Published: March 2024

Context. Observations of z ∼ 6 quasars powered by supermassive black holes (SMBHs; MBH ∼ 108 − 10 M⊙) challenge our current understanding of early black hole (BH) formation and evolution. The advent of the James Webb Space Telescope (JWST) has enabled the study of massive BHs (MBHs; MBH ∼ 106 − 7 M⊙) up to z ∼ 11, thus bridging the properties of z ∼ 6 quasars to their ancestors.

Aims. The JWST spectroscopic observations of GN-z11, a well-known z = 10.6 star-forming galaxy, have been interpreted with the presence of a super-Eddington (Eddington ratio ≡ λEdd ∼ 5.5) accreting MBH. To test this hypothesis, we used a zoom-in cosmological simulation of galaxy formation and BH co-evolution.

Methods. We first tested the simulation results against the observed probability distribution function (PDF) of λEdd found in z ∼ 6 quasars. Then, in the simulation we selected the BHs that satisfy the following criteria: (a) 10 < z < 11, (b) MBH > 106 M⊙. Next, we applied the extreme value statistics to the PDF of λEdd resulting from the simulation.

Results. We find that the probability of observing a z ∼ 10 − 11 MBH accreting with λEdd ∼ 5.5 in the volume surveyed by JWST is very low (< 0.2%). We compared our predictions with those in the literature, and discussed the main limitations of our work.

Conclusions. Our simulation cannot explain the JWST observations of GN-z11. This might be due to: (i) poor resolution and statistics in simulations, (ii) simplistic sub-grid models (e.g. BH accretion and seeding), (iii) uncertainties in the data analysis and interpretation.
Differential optical transfer function (dOTF) broad-spectrum wavefront sensing using integral field unit spectroscopy
Authors: Martinez P.
Published: March 2024

Context.Detecting and characterizing Earth-like exoplanets is a critical scientific goal for the next generation of telescopes. However, current direct imaging instruments are hindered by evolving noncommon path aberrations (NCPAs), which lead to persistent speckles in the images. The differential optical transfer function (dOTF) is an image-based, noniterative, and model-independent wavefront sensor that combines differential images to estimate the complex field of the pupil.

Aims.Given the objective of spectrally characterizing exoplanets to discern their composition and potentially detect biosignatures, we aim to explore the integration of the dOTF sensing method with an integral field unit (IFU) spectrograph. An IFU spectrograph generates a spectral data cube that contains diverse spectral information within a single dataset. Combining these two concepts is expected to improve the efficiency with which NCPAs can be spectrally measured and characterized.

Methods.This Letter presents an implementation strategy for integrating dOTF and IFU spectroscopy data, enabling estimations of the electric field at various wavelengths simultaneously.

Results.This method is specifically optimized to provide the most effective combination with minimal hardware requirements. It involves the use of multiple simultaneous deformable mirror actuator displacements in conjunction with an adapted Lyot stop employing a circular variable filter.

Conclusions.The dOTF wavefront sensor coupled with an IFU spectrograph promises to be rapid and efficient, capable of measuring NCPAs across the entire spectrum provided by the spectrograph. Because the combination of dOTF and IFU spectroscopy is immediately applicable, it is of potential interest for various present-day on-sky instruments, as well as future IFU-based instruments coupled to the next generation of extremely large telescopes (ELTs).
Endokrine Therapielandschaft bei Patient*innen mit HR+ HER2− frühem Mammakarzinom in Deutschland vor Einführung der CDK4/6-Inhibitor-Behandlung – eine Real-World-Analyse
Authors: Nabieva Naiba , Altmann Falk , Apel Klaus , Baerens Dirk-Toralf , Beha Michaela , Belau Antje , Busch Steffi , Guth Dagmar , Heinrich Georg , Kreiss-Sender Janine , Markmann Susanne , Olbermann Andreas , Oskay-Özcelik Gülten , Schuback Beatrix , Steinfeld-Birg Dieter , Quiering Claudia , Kiss Ferenc , Kreuzeder Julia , Nuti Paolo , Schilling Jörg
Published: March 2024

Einleitung Während prämenopausale Patientinnen mit einem HR+ HER2− frühen Mammakarzinom mit Tamoxifen +/− ovarielle Suppression mit einem GnRH-Analogon oder einem Aromataseinhibitor (AI) + GnRH behandelt werden, erhalten postmenopausale Frauen vorwiegend einen AI aufgrund der besseren Wirksamkeit verglichen mit Tamoxifen. Da es durch den Einzug der CDK4/6-Inhibitoren in die Behandlung des frühen Mammakarzinoms mit höherem Rückfallrisiko vermutlich zu einer Verschiebung der endokrinen Therapielandschaft kommt, ist von Interesse, wie in Deutschland potenzielle CDK4/6-Inhibitor-Kandidat*innen vor deren Markteinführung behandelt wurden.

Patienten und Methoden Im Rahmen einer retrospektiven, multizentrischen Analyse wurden anonymisierte Daten von Patient*innen mit einem HR+ HER2− frühen Mammakarzinom und einer im Zeitraum zwischen 10/2021–03/2022 begonnenen Antihormontherapie erhoben. Potenzielle CDK4/6-Inhibitor-Kandidat*innen wurden anhand der Einschlusskriterien der NATALEE- und monarchE-Studien in entsprechende Risikokollektive unterteilt.

Ergebnisse Insgesamt wurden Daten von 238 Patient*innen aus 29 Zentren analysiert. Während den monarchE-Kriterien 20,6 % der Patient*innen zugeordnet werden konnten, enthielt das NATALEE-ähnliche Kollektiv 46,2 % der Patient*innen. 53,8 % der Patient*innen erfüllten weder die Einschlusskriterien der NATALEE- noch die der monarchE-Studie. Über die Hälfte der Patient*innen erhielt keine Chemotherapie. Im Gesamtkollektiv waren 28,6 % der Patientinnen prämenopausal. 67,6 % der prämenopausalen Frauen wurden mit einer neo-/adjuvanten Chemotherapie behandelt. 61,8 % der prämenopausalen Patientinnen erhielten als adjuvante Antihormontherapie Tamoxifen, 19,1 % AI + GnRH und 10,3 % Tamoxifen + GnRH.

Schlussfolgerung Trotz des hohen Anteils prämenopausaler Patientinnen, die mit einer aggressiven Therapie im Sinne einer Chemotherapie behandelt wurden, wurde bei nur einem Drittel der prämenopausalen Patientinnen GnRH zur Antihormontherapie hinzugenommen. Untersuchungen zu einem späteren Zeitpunkt sowie Registerstudien sind nötig, um zu sehen, wie sich durch den Einzug der CDK4/6-Inhibitoren die endokrine Therapielandschaft in Deutschland verändert.
Developing Systems of Care for Stroke in Resource-limited Settings
Authors: Silva Gisele Sampaio , Rocha Eva
Published: March 2024

Although stroke prevention and treatment strategies have significantly advanced in recent years, implementation of these care elements in resource-limited settings can be challenging, since the burden of stroke is higher and access to stroke care is lower. Barriers to stroke care in resource-limited settings include insufficient prevention, reduced awareness of stroke symptoms, limited prehospital care and lack of triage systems, limited access to comprehensive stroke centers, inadequate personnel education, lack of staff and resources, as well as limited access to neuroimaging, thrombolytics, mechanical thrombectomy, neurosurgical care, and rehabilitation. Here, we suggest strategies to improve stroke care in these settings, including public health campaigns, protocols for prehospital notification, organized flow to specialized stroke centers, development of dedicated stroke units, and utilization of telemedicine and telerehabilitation. We also highlight the role of international organizations and governments in reducing the global burden of stroke.
Nanophotonic phased array XY Hamiltonian solver
Authors: Chalupnik Michelle , Singh Anshuman , Leatham James , Lončar Marko , Soltani Moe
Published: March 2024

Solving large-scale computationally hard optimization problems using existing computers has hit a bottleneck. A promising alternative approach uses physics-based phenomena to naturally solve optimization problems, wherein the physical phenomena evolve to their minimum energy. In this regard, photonics devices have shown promise as alternative optimization architectures, benefiting from high-speed, high-bandwidth, and parallelism in the optical domain. Among photonic devices, programmable spatial light modulators (SLMs) have shown promise in solving large scale Ising model problems, to which many computationally hard problems can be mapped. Despite much progress, existing SLMs for solving the Ising model and similar problems suffer from slow update rates and physical bulkiness. Here, we show that using a compact silicon photonic integrated circuit optical phased array (PIC-OPA), we can simulate an XY Hamiltonian, a generalized form of the Ising Hamiltonian, where spins can vary continuously. In this nanophotonic XY Hamiltonian solver, the spins are implemented using analog phase shifters in the optical phased array. The far field intensity pattern of the PIC-OPA represents an all-to-all coupled XY Hamiltonian energy and can be optimized with the tunable phase-shifters, allowing us to solve an all-to-all coupled XY model. Our results show the utility of PIC-OPAs as compact, low power, and high-speed solvers for nondeterministic polynomial-hard problems. The scalability of the silicon PIC-OPA and its compatibility with monolithic integration with CMOS electronics further promise the realization of a powerful hybrid photonic/electronic non-Von Neumann compute engine.
Profiling English sentences based on CEFR levels
Authors: Uchida Satoru , Arase Yuki , Kajiwara Tomoyuki
Published: March 2024

The study aims to demonstrate the procedure for constructing the CEFR-based Sentence Profile (CEFR-SP), a dataset
with the CEFR levels assigned for sentences, and to identify the characteristics at each level. Basic statistics such as word
length and sentence length are presented for each CEFR level for 7,511 carefully selected sentences, and statistical tests are
conducted between adjacent levels to identify criterial features. The findings reveal significant differences in word length
between adjacent levels, while word difficulty is not significant in discriminating levels at either end (A1–A2, C1–C2). Sentence
length and depth are also not significant discriminators for higher levels (B2–C1, C1–C2). Notably, sentence-level data generally
exhibit discriminative values compared to text-level statistics, indicating their direct capture of characteristics at each CEFR
level.
Grim humor in the tale of the wolf’s death
Authors: Nieuwenhuis Mark
Published: March 2024

Contrary to other episodes of the Ysengrimus, the final episode in the seventh book of the
Flemish animal epic is not based upon a known animal fable. The narrative core seems to be the story of the death of the prophet
Muhammad as told by Embrico of Mainz. In this article I argue that the poet of the Ysengrimus may also have used
elements from Ovid’s tale of Pentheus and the maenads in the third book of the Metamorphoses, just as the wolf’s
eschatological prophesy might be an intertextual play on the storm scene in the first book of the Aeneid.
Following this, I elaborate some clues that lend support to the idea, previously presented in the literature, that the portrayal
of the sow Salaura refers to Hildegard of Bingen and her visions, publicly acknowledged by Pope Eugenius III during the Synod in
Trier in 1147–1148, just before the completion of Ysengrimus.
De canicula lacrimante
Authors: Perrier-Gros-Claude Alexia
Published: March 2024

Abstraite

La Disciplina Clericalis de Pierre Alphonse est une œuvre du xii
e siècle dont
le contenu s’articule autour de trois axes thématiques principaux qui sont, successivement, les vices et les vertus, les
relations de l’homme avec ses semblables, et avec Dieu. Elle a connu un grand succès en Europe, comme le montre
l’existence de soixante manuscrits conservés et la présence de plusieurs récits dans de célèbres recueils
d’exempla. Tel est le cas de la narration “De canicula lacrimante” (“La petite
chienne qui pleure”) que nous retrouvons, par exemple, en Espagne, dans le Libro de los exemplos por A. B. C. de
Clemente Sánchez de Vercial, datant du xv
e siècle. Cet exemplum, le treizième de la
collection, fait partie d’une série de récits dont le thème est la ruse féminine, et s’avère particulièrement
intéressant à étudier car il raconte comment une vieille entremetteuse se sert d’une chienne pour élaborer un stratagème
afin de convaincre une femme chaste de tromper son mari: elle lui fait croire que sa propre fille s’est transformée en
animal après avoir rejeté les avances d’un prétendant. Cette donnée place la narration dans la tradition littéraire des
récits de métamorphoses; ainsi, nous nous intéresserons d’abord à la métamorphose canine et son symbolisme, avant de
montrer que la petite chienne est au centre de la création d’une fausse merveille originale, basée sur une ‘diabolique’
instrumentalisation des larmes.1
MT error detection and correction by Chinese language learners
Authors: Zhang Qi , Osborne Caitríona , Moorkens Joss
Published: March 2024

This article analyzes texts that have been generated by machine translation (MT) and post-edited by native
English-speaking trainee translators (English>Chinese) who are also Chinese language learners enrolled in a four-year
undergraduate translation program. The project examines the work product of trainee translators to categorize 122 errors that are
(un)noticed and (un)corrected by them. MT errors in the Accuracy category were best identified and corrected, followed by those in
the Lexicon and Fluency categories. Trainee translators who were advanced language learners outperformed the intermediate group in
MT error detection and correction, especially in the Lexicon category. This study sheds light upon the use of raw MT output as
meaningful input for trainee translators who are in the process of learning Chinese. Its findings provide information regarding
the type of exercises needed in language learning and translation training for students with different levels of language
proficiency.
Dynamics of chaotic and hyperchaotic modified nonlinear Schrödinger equations and their compound synchronization
Authors: Abed-Elhameed Tarek M , Otefy Mohamed , Mahmoud Gamal M
Published: March 2024

We present in this paper four versions of chaotic and hyperchaotic modified nonlinear Schrödinger equations (MNSEs). These versions are hyperchaotic integer order, hyperchaotic commensurate fractional order, chaotic non-commensurate fractional order, and chaotic distributed order MNSEs. These models are regarded as extensions of previous models found in literature. We also studied their dynamics which include symmetry, stability, chaotic and hyperchaotic solutions. The sufficient condition is stated as a theorem to study the existence and uniqueness of the solutions of hyperchaotic integer order MNSE. We state and prove another theorem to test the dependence of the solution of hyperchaotic integer order MNSE on initial conditions. By similar way, we can introduce the previous two theorems for the other versions of MNSEs. The Runge-Kutta of the order 4, the Predictor-Corrector and the modified spectral numerical methods are used to evaluate the numerical solutions for integer, fractional and distributed orders MNSEs, respectively. We calculate numerically using the Lyapunov exponents the intervals of parameters of the purposed models at which hyperchaotic, chaotic and stable solutions are exist. The MNSEs have an important role in many fields of science and technology, such as nonlinear optics, electromagnetic theory, superconductivity, chemical and biological dynamics, lasers and plasmas. The compound synchronization for these chaotic and hyperchaotic models is investigated. We state its scheme using the tracking control technique among three integer commensurate and non-commensurate orders as the derive models and one distributed order as a slave model. We presented and proved a theorem that provides us with the analytical formula for the control functions which are required to achieve compound synchronization. The analytical results are supported by numerical calculations and agreement is found.
Four-channel holographic metasurface based on frequency-angle multiplexing
Authors: Dong Liang , Li Yang , Wei Jinxu , Zhu Lei
Published: March 2024

Due to the powerful ability of metasurfaces to manipulate light fields, various optical parameters have been widely explored and studied through precise design of metasurface units. However, the angle of incidence, which is one of the important optical parameters, has not been fully investigated for multiplexing due to the lack of coding degrees of freedom. Here, the scheme of four-channel holographic metasurface based on frequency-angle multiplexing is proposed to achieve independent display of multiple images at different frequencies and angles. The metasurface units used are Metal-Insulator-Metal structures that can effectively manipulate the electromagnetic wave’s amplitude in the reflection space to accommodate various operating frequencies and angles of incidence. The effectiveness of the proposed four-channel holographic scheme is verified by encoding four independent amplitude image information into a metasurface array. The four-channel scheme proposed in this paper successfully breaks the limitation of angular correlation and improves the density and capacity of information storage. This not only provides a higher degree of freedom and flexibility for multi-channel metasurface holographic imaging, but also holds significant importance for advancing optical information processing and display technologies. It is believed that the metasurface based on frequency-angle multiplexing can easily find more promising applications, including electromagnetic wavefront control, encryption/ concealment of optical information, and multifunctional switchable devices.
A novel analytical approach to the Benjamin–Ono equation
Authors: Yel Gülnur , Bulut Hasan , Kemaloglu Beyhan
Published: March 2024

This article examines some travelling wave solutions to the second-order Benjamin-Ono equation by using an analytical scheme via the sine-Gordon expansion technique. The Benjamin-Ono equation is similar to the KdV equation and it describes internal waves in fluids in a deep layer. We achieved some travelling wave solutions, including hyperbolic functions. All the obtained solutions were graphically analyzed based on their physical properties. As a result, the mentioned method is an effective one that provides analytical solutions for strongly non-linear partial differential models.
Pair induced quenching in high concentration Holmium-doped fiber amplifiers
Authors: Mirza Jawad , Ghafoor Salman , Almogren Ahmad , Ahmad Salaria Umair , Kanwal Benish , Aziz Imran , Atieh Ahmad
Published: March 2024

The spectrum required for future optical communication systems is being extended towards the C-, L- and U-bands, resulting in a significant interest in the spectral region around 2 μm wavelength. Since Holmium doped fiber amplifiers (HDFAs) provide amplification in this spectral region, they have become a focus of researchers working on doped fiber amplifiers. A major factor resulting in the performance degradation of HDFAs is the inhomogeneous energy transfer within Ho3+ ion-pairs in high-concentration Holmium-doped fibers (HDFs), an effect generally known as pair-induced quenching (PIQ). In this paper, we study the luminal and temporal dynamics of pulses of different repetition rates at 2.05 μm in high-concentration HDFs considering the effects of ion-pairs. Input pulses having repetition rates of 25 GHz and 500 kHz are generated using wavelength tunable actively mode-locked Holmium-doped fiber laser (AML-HDFL) based on a single ring cavity and bidirectional pumping. The characteristics of the pulses propagating through high-concentration HDF are analyzed based on different metrics such as average power, peak power, pulse energy, full-width at half maximum (FWHM), and time delay without and with ion-pairs for values of fraction of ion-pairs k = 0 and k = 10%, respectively. The results obtained at optimized length of HDF show that ion-pairs significantly degrade the average power, peak power, and energy of the output pulses for both of the repetition rates. For both k = 0 and k = 10%, the FWHM and shape of the output pulses remain same in the presence of the ion-pairs while, time delay of 4 ps and 19 ns is observed in the output pulses at repetition rates of 25 GHz and 500 kHz, respectively. The effects of increasing the pump and signal power on the average power and energy of the output pulses for k = 0 and k = 10% are also discussed for both repetition rates. This analysis provides important guidelines for designers of 2 μm fiber lasers and amplifiers based on high-concentration HDFs.
Reliable formulas for accurately determining the resonance and antiresonance frequencies of thin film bulk acoustic resonators
Authors: Zhang Dapeng , Chen Zheng-You , Re-Ching Lin , Sun Shih-Jye
Published: March 2024

Expanding upon Lakin’s theory by considering the phase shift of the acoustic waves in the metallic layers, we have developed an impedance formula for a piezoelectric layer covered by a finite thickness of metal layers, enabling the precise determination of its resonant and anti-resonant frequencies. Compared to experimental data and 3D finite element simulations, our formula can accurately and quickly predict resonant, anti-resonant frequencies, and bandwidth across a wide range of piezoelectric and metallic layer thickness combinations.
Reanalysis of energy band structure in the type-II quantum wells
Authors: Li 李 Xinxin 欣欣 , Deng 邓 Zhen 震 , Jiang 江 Yang 洋 , Du 杜 Chunhua 春花 , Jia 贾 Haiqiang 海强 , Wang 王 Wenxin 文新 , Chen 陈 Hong 弘
Published: March 2024

Band structure analysis holds significant importance for understanding the optoelectronic characteristics of semiconductor structures and exploring their potential applications in practice. For quantum well structures, the energy of carriers in the well splits into discrete energy levels due to the confinement of barriers in the growth direction. However, the discrete energy levels obtained at a fixed wave vector cannot accurately reflect the actual energy band structure. In this work, the band structure of the type-II quantum wells is reanalyzed. When the wave vectors of the entire Brillouin region (corresponding to the growth direction) are taken into account, the quantized energy levels of the carriers in the well are replaced by subbands with certain energy distributions. This new understanding of the energy bands of low-dimensional structures not only helps us to have a deeper cognition of the structure, but also may overturn many viewpoints in traditional band theories and serve as supplementary to the band theory of low-dimensional systems.
Bone morphogenetic protein-2 loaded triple helix recombinant collagen-based hydrogels for enhancing bone defect healing
Authors: He Huixia , Yang Fan , Zhang Shanshan , Liu Zhao , Liu Zaiman , Yu Linghui , Xiao Jianxi
Published: March 2024

The development of efficacious bone substitute biomaterials remains a major challenge for research and clinical surgical. Herein, we constructed triple helix recombinant collagen (THRC) -based hydrogels loading bone morphogenetic protein-2 (BMP-2) to stimulate bone regeneration in cranial defects. A series of in situ forming hydrogels, denoted as THRC-oxidized carboxymethylcellulose (OCMC)-N-succinyl-chitosan (NSC) hydrogels, was synthesized via a Schiff base reaction involving OCMC, THRC and NSC. The hydrogels underwent rapid formation under physiological pH and temperature conditions. The composite hydrogel exhibits a network structure characterized by uniform pores, the dimensions of which can be tuned by varying THRC concentrations. The THRC-OCMC-NSC and THRC-OCMC-NSC-BMP2 hydrogels display heightened mechanical strength, substantial biodegradability, and lower swelling properties. The THRC-OCMC-NSC hydrogels show exceptional biocompatibility and bioactivity, accelerating cell proliferation, adhesion, and differentiation. Magnetic resonance imaging, computed tomography and histological analysis of rat cranial defects models revealed that the THRC-OCMC-NSC-BMP2 hydrogels substantially promote new bone formation and expedite bone regeneration. The novel THRC-OCMC-NSC-BMP2 hydrogels emerge as promising candidates for bone substitutes, demonstrating substantial potential in bone repair and regeneration applications.
The effect of magnesium ions synergistic with mineralized collagen on osteogenesis/angiogenesis properties by modulating macrophage polarization in vitro and in vivo
Authors: Liu Chang , Ma Nan , Sun Changan , Shen Xuecheng , Li Jinwei , Wang Chengyue
Published: March 2024

In bone tissue engineering, the bone immunomodulatory properties of biomaterials are critical for bone regeneration, which is a synergistic process involving physiological activities like immune response, osteogenesis, and angiogenesis. The effect of the macrophage immune microenvironment on the osteogenesis and angiogenesis of various material extracts was examined in this experiment using Mg2+ and Nano-hydroxyapatite/collagen (nHAC) in both a single application and a combined form. This study in vitro revealed that the two compounds combined significantly inhibited the NF-κB signaling pathway and reduced the release of inflammatory factors from macrophages when compared with the extraction phase alone. Additionally, by contributing to the polarization of macrophages towards the M2 type, the combined effects of the two materials can significantly improve osteogenesis/angiogenesis. The results of in vivo experiments confirmed that Mg2+/nHAC significantly promoted bone regeneration and angiogenesis. This study offers a promising method for enhancing bone graft material osseointegration.
Flow patterns at river bends and its response to surrounding infrastructures
Authors: Pinasti N W , Wijayanti E , Nurfaida W , Sulaiman M , Kurniawan A
Published: March 2024

On January 6, 2023, high-intensity precipitation occurred in the Babon River watershed, causing the river overflow and flood in several areas. Severe impact in the surrounding area was observed, such as in the Dinar Indah Housing Complex. Hydrodynamic complexity around a river bend points out the importance of understanding the flow patterns at a river bend. Therefore, this study aimed to describe the flow pattern of the river bend and analyze its response to the surrounding infrastructure using the HEC-RAS 6.3 model. Furthermore, improvement to structural mitigation was also designed. Field observations were also conducted to gather field data on the flood impact. The model results indicate that the highest water level within the river bend is 1.9 m, and the highest velocity is 5.85 m/s, which is on the outer bend. A dyke was then planned to be about 3.75 meters high, accompanied by a retaining wall to protect the river bank using the interlocking permeable revetment (IPR). Dyke and retaining walls provide stability against shear, overturning, and collapse.
Double sill stilling basin to enhance energy dissipation for a strong hydraulic jump with a high Froude number
Authors: Erryanto S , Dermawan V
Published: March 2024

Roller Compacted Concrete (RCC) is a new and viable construction material for concrete gravity dams. It is gaining popularity due to its low cost and fast deployment. The design of a stilling basin, part of a dam that controls the hydraulic jump and dissipates energy, is crucial. One of the important considerations is the Froude number at the spillway toe (F1), which determines the type of hydraulic jump that will occur. An energy dissipator is also required to prevent scour caused by the change in flow conditions from supercritical to subcritical. Double sills installed downstream of the steep chute way channel can be used as an energy dissipator. This study uses hydraulic modeling to evaluate the flow energy reduction and subcritical flow conditions in a stilling basin with double sills. The investigation is expected to provide better information on hydraulic jump control.
Effect of equilibrium and non-equilibrium sediment transport flows on the shear velocity in an open channel.
Authors: Maini M , Kironoto B A , Rahardjo A P , Istiarto
Published: March 2024

Equilibrium and non-equilibrium sediment transport flow in natural rivers and artificial channels can result in degradation or aggradation of the river bed, which will affect many hydraulic parameters, one of which is shear velocity. This study evaluates the influence of sediment transport on shear velocity in open channels. In this study, laboratory experiments were carried out using a sediment-recirculating flume, and measurements of the velocity and Reynolds shear stress distributions were measured using a Sontek-acoustic Doppler velocimeter (ADV). This experimental study measured 120 velocity distributions, and Reynolds stress profiles, consisting of 12 different sets of measurements involving flow with sediment transport and movable sand bed. The results showed an average shear velocity, u*, difference between sediment feeding and without sediment feeding by 9.41%. For the integration constant Br value, the average difference between sediment feeding and without sediment feeding was 5.58%.
Prediction of sediment transport due to detached breakwater
Authors: Saputra A , Sumiadi
Published: March 2024

This research intends to predict the pattern and accumulation of sediment transport before and after being built the detached breakwater. This research was conducted on Matras, Penyak, and Pasir Padi shorelines which are located in Bangka Island-Indonesia. Based on the previous research, few empirical methods are used for analyzing the shore response due to the breakwater for fulfilling the erosion and sedimentation in the shoreline. However, there has not been more research that analyzed the effect of breakwater itself on the pattern and accumulation of sediment transport (the formation of tombolo and salient) that happens in the shorelines based on the parameters of structure, physical condition, and characteristics of sediment. The research methodology consists of collecting data, measurement on the field, and Citra satellite observation without and with breakwater. The result is hoped can support the modelling of the distance among breakwaters and the effective formulation of the distance among breakwaters.
Mapping groundwater potential zone using groundwater potentiality index in Sulamu, Central Fatuleu and West Fatuleu, Kupang, East Nusa Tenggara
Authors: Adelin A N , Hartono H I R , Putra D P E , Pranantya P A
Published: March 2024

Water scarcity often occurs during the dry season in Kupang Regency, which is a semi-arid area. The drought limits surface water availability during the dry season, thus making groundwater one of the reliable solutions for fulfilling the need for water from springs and wells. Therefore, mapping the potential of groundwater in the research area becomes the aim of this study, which has never been conducted before. The method used in this research is the Groundwater Potentiality Index, which uses five parameters to identify groundwater potential areas: fracture, lithology, topography, drainage, and rainfall. Field observation and secondary data collection were conducted to provide those parameters. The results are groundwater potential index classified into five groundwater potential zones, resulting in very low (17.07% and 20.39% of total area), low (51.16% and 48.94% of total area), moderate (26.9% and 27.05% of total area), high (4.09% and 3.1% of total area), and very high (0.77% and 0.53% of total area). Zones of very high are found along major fault areas. Areas with high groundwater potential zones indicated favorable conditions for wells positioning at groundwater exploration. These results can be a basis for action related to groundwater resource development in the research area.
Groundwater investigation in the Batang Integrated Industrial Park, Central Java, Indonesia
Authors: Widyatama F X G S , Wilopo W , Broto S A
Published: March 2024

Batang Integrated Industrial Park (BIIP), Central Java, Indonesia, needs the support of water sources, one of which is groundwater. In addition, industrial waste also can contaminate the groundwater. Therefore, assessing groundwater potential and quality is vital for an environmental baseline to manage sustainable groundwater resources. This research aims to identify the subsurface geology, especially the aquifer system and physicochemicals of groundwater, unprecedented in BIIP. The aquifer system determined the research method through geological surface mapping and geoelectrical surveys. Physicochemical properties, including temperature, pH, total dissolved solids (TDS), and electrical conductivity (EC), were directly measured in wells and springs in the industrial areas. The result shows that the BIIP is dominated by sand, silt, and clay, with sand as the primary aquifer located in-depth 1.35 to 47 meters, concentrated mainly in the western region and towards the east, decreasing as an unconfined aquifer. Groundwater flows from the south toward the Java Sea in the north. Groundwater has a temperature of around 27.3–30.9°C, pH 5.26–7.47, TDS 49–568 mg/L, and EC 100 – 613 μs/cm. It indicates that the quality and quantity of groundwater in the BIIP are quite suitable for use as raw water.
Performance assessment of reservoir storage capacity
Authors: Trimartinni A D , Limantara L M
Published: March 2024

This research intends to assess the performance of reservoir capacity. The performance of reservoir capacity indicates the reliability in guaranteeing the water supply need. However, this assessment of reservoir storage capacity is based on the variability coefficient of hydrology conditions. The methodology consists of data collecting that includes the historical discharge that is used for analyzing the variation coefficient of yearly discharge (Cv), water need based on the yearly discharge ratio (D), and storage capacity over the year (Ka). The performance of reservoir storage capacity uses the regression equation of Mc Mahon and Adeloye. The result shows that Indonesia’s reservoir storage capacity is well performing only for fulfilling the water need demand of about 0.0001 to 0.15 of yearly average discharge. However, the negative NSE value is obtained for water demand about 0.2 until 0.55 of yearly average discharge. It shows that the storage capacity observed is under-estimate if it is for supplying the water need demand with a ratio of more than 0.2 of yearly average discharge. This research result is hoped to predict the feasibility of reservoir storage capacity. In addition, it can be used as a reference in assessing the performance of multipurpose reservoir storage capacity as the base of accurate decision taking in planning reservoir storage capacity and reservoir utilization. Then, it is the base of decision taking in designing the dimensions of dam complementary buildings.
Assessing the impact of climate change on surface runoff of the Ubolratana Reservoir, Thailand
Authors: Suryani N S , Pawattana C , Lohpaisankrit W , Muangthong S
Published: March 2024

Assessing surface runoff in river basins is paramount for effectively managing water resources. Climate change significantly impacts the availability of water within these basins. The Ubolratana reservoir is vital for sustainable water supply, aquaculture, agricultural practices, and domestic needs. This research aims to evaluate the runoff availability of the reservoir by using the Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) under distinct climate change scenarios. The HEC-HMS model was calibrated based on observed rainfall and runoff data. To project future runoff dynamics, calibrated model parameters were coupled with the bias-corrected rainfall data of Can-ESM5, CESM2, and GFDL-ESM4 models for two Shared Socioeconomic Pathways (SSPs) climate scenarios (SSP 245 and SSP 585). The results show upward trends in both projected rainfall and runoff within the drainage area of the Ubolratana reservoir between 2022 and 2061. In summary, the findings of this research may be useful for regional water resources management and strategic planning endeavors.
Evaluation of irrigation channels in the dry season at Dadahup swamp irrigation area to strengthen food security
Authors: Wahyuni A , Sujono J , Istiarto
Published: March 2024

Dadahup swamp irrigation area is included in the food estate project location. The government has rehabilitated irrigation networks to support the program in 2020. A good agricultural system should be supported by water availability to fulfill irrigation water needs. The obstacle often faced in agriculture is usually the water deficit that occurs in the dry season. Corn is usually cultivated in the dry season to reduce water irrigation demand and cannot be inundated with water for long. This study aims to determine the water availability in the irrigation channels to supply water needs for corn. The Storm Water Management Model is used to perform hydraulic analysis in irrigation channels. The results showed that the water levels ranged from +0.04 m to 0.49 m in irrigation channels, while the ground elevations ranged from +1.12 m to 1.74 m. Due to water levels in the irrigation channels below the ground elevation, the Blok A5 Kanan can be proposed for corn cultivation in the dry season. This study’s outcome will be increased crop productivity, achieving sustainable agriculture.