bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the track of the GD-1 stellar stream inside a host with a fermionic dark matter core-halo distribution
Authors: Mestre Martín Federico , Argüelles Carlos Raul , Carpintero Daniel Diego , Crespi Valentina , Krut Andreas
Published: June 2024

Context. Traditional studies of stellar streams typically involve phenomenological ΛCDM halos or ad hoc dark matter (DM) profiles with different degrees of triaxiality, which preclude us from gaining insights into the nature and mass of the DM particles. Recently, the maximum entropy principle of halo formation has been applied to provide a DM halo model that incorporates the fermionic (quantum) nature of the particles while leading to DM profiles that depend on the fermion mass. These profiles develop a more general “dense core – diluted halo” morphology that can explain the Galactic rotation curve, while the degenerate fermion core can mimic the central massive black hole (BH).

Aims. We model the GD-1 stellar stream using a spherical core-halo DM distribution for the host that simultaneously explains the dynamics of the S-cluster stars through its degenerate fermion core without a central BH.

Methods. We used two optimization algorithms in order to fit both the initial conditions of the stream orbit and the fermionic model. We modeled the baryonic potential with a bulge and two disks (thin and thick) with fixed parameters according to the recent literature. The stream observables were 5D phase-space data from the Gaia DR2 survey.

Results. We were able to find good fits for both the GD-1 stream and the S-stars for a family of fermionic core-halo profiles parameterized by the fermion mass. The particle masses are constrained in the range 56 keV c−2, with a corresponding DM core of ∼103 Schwarzschild radii, to 360 keV c−2, which corresponds to the most compact core of 5 Schwarzschild radii prior to the gravitational collapse into a BH of about 4 × 106 M⊙.

Conclusions. This work provides evidence that the fermionic profile is a reliable model for the massive central object and for the DM of the Galaxy. Remarkably, this model predicts a total Milky Way mass of 2.3 × 1011 M⊙, which agrees with recent mass estimates obtained from Gaia DR3 rotation curves (Gaia RC). In summary, with one single fermionic model for the DM distribution of the Milky Way, we obtain a good fit on three totally different distance scales of the Galaxy: ∼10−6 kpc (central, S-stars), ∼14 kpc (middle, GD-1), and ∼30 kpc (boundary, Gaia RC mass estimate).
Molecular gas excitation in the circumgalactic medium of MACS1931–26
Authors: Ghodsi L. , Zhou J. , Andreani P. , De Breuck C. , Man A. W. S. , Miyamoto Y. , Bisbas T. G. , Lundgren A. , Zhang Z.-Y.
Published: June 2024

The evolution of galaxies is largely affected by exchanging material with their close environment, the circumgalactic medium (CGM). In this work, we investigate the CGM and the interstellar medium (ISM) of the bright central galaxy (BCG) of the galaxy cluster, MACS1931−26 at z ∼ 0.35. We detected [CI](2−1), 12CO(1−0), and 12CO(7−6) emission lines with the APEX 12-m and NRO 45-m telescopes. We complemented these single-dish observations with 12CO(1−0), 12CO(3−2), and 12CO(4−3) ALMA interferometric data and inferred the cold molecular hydrogen physical properties. Using a modified large velocity gradient (LVG) model, we modelled the CO and CI emission of the CGM and BCG to extract the gas thermodynamical properties, including the kinetic temperature, the density, and the virialisation factor. Our study shows that the gas in the BCG is highly excited, comparable to the gas in local ultra luminous infrared galaxies (ULIRGs), while the CGM is likely less excited, colder, less dense, and less bound compared to the ISM of the BCG. The molecular hydrogen mass of the whole system derived using [CI](2−1) is larger than the mass derived from 12CO(1−0) in literature, showing that part of the gas in this system is CO-poor. Additional spatially resolved CI observations in both transitions, [CI](1−0) and [CI](2−1), and the completion of the CO SLED with higher CO transitions are crucial to trace the different phases of the gas in such systems and constrain their properties.
The fountain of the luminous infrared galaxy Zw049.057 as traced by its OH megamaser
Authors: Lankhaar Boy , Aalto Susanne , Wethers Clare , Moldon Javier , Beswick Rob , Gorski Mark , König Sabine , Yang Chentao , Mangum Jeff , Gallagher John , Combes Françoise , Rigopoulou Dimitra , González-Alfonso Eduardo , Muller Sébastien , Garcia-Bernete Ismael , Henkel Christian , Nishimura Yuri , Ricci Claudio
Published: June 2024

High-resolution ($ 0{{\overset{\prime\prime}{.}}}037{-}0{{\overset{\prime\prime}{.}}}13 $ [10 − 35 pc]) e-MERLIN (λ6 − 18 cm) and ($ 0{{\overset{\prime\prime}{.}}}024 $ [6.5 pc]) ALMA (λ1.1 mm) observations have been used to image OH (hydroxyl) and H2CO (formaldehyde) megamaser emission, and HCN 3 → 2 emission toward the nuclear (< 100 pc) region of the luminous infrared galaxy Zw049.057. Zw049.057 hosts a compact obscured nucleus (CON), and thus represents a class of galaxies that are often associated with inflow and outflow motions. Formaldehyde megamaser emission has been detected toward the nuclear region, ≲30 pc ($ 0{{\overset{\prime\prime}{.}}}1 $), and traces a structure along the disk major axis. OH megamaser (OHM) emission has been detected along the minor axis of the disk, ∼30 pc ($ 0{{\overset{\prime\prime}{.}}}1 $) from the nucleus, where it exhibits a velocity gradient with extrema of −20 km s−1 southeast (SE) of the disk and −110 km s−1 northwest (NW) of the disk. HCN 3 → 2 emission reveals extended emission, along the disk minor axis out to ∼60 pc ($ 0{{\overset{\prime\prime}{.}}}2 $). Analysis of the minor axis HCN emission reveals high-velocity features extending out to 600 km s−1, redshifted on the SE side and blueshifted on the NW side. We propose that the high-velocity HCN emission traces a fast (> 250 km s−1) and collimated outflow that is enveloped by a wide-angle and slow (∼50 km s−1) outflow that is traced by the OHM emission. Analysis of the outflow kinematics suggests that the slow wide-angle outflow will not reach escape velocity and will instead fall back to the galaxy disk, evolving as a so-called fountain flow, while the fast collimated outflow traced by HCN emission will likely escape the nuclear region. We suggest that the absence of OHM emission in the nuclear region is due to high densities there. Even though OHMs associated with outflows are an exception to conventional OHM emission, we expect them to be common in CON sources that host both OHM and H2CO megamasers.
The unexpected role of heliospheric boundaries in facilitating interstellar dust penetration at 1–5 AU
Authors: Godenko E. A. , Izmodenov V. V.
Published: June 2024

Aims.Interstellar dust (ISD) particles penetrate the heliosphere because of the relative motion of the local interstellar cloud and the Sun. The penetrated particles pass through the heliospheric interface, that is, the region in which solar wind and interstellar plasma interact. As a result, the ISD flow is modified after the passage through this region under the influence of electromagnetic force. The main goal of this work is to show how the heliospheric interface affects the distribution of ISD particles near the Sun.

Methods.We have developed a Monte Carlo model of the ISD distribution in the heliosphere. It first takes the effects of the heliospheric interface and the rotating heliospheric current sheet into account. The effects of the heliospheric interface were probed using a global heliospheric model.

Results.The computation results show that the heliospheric interface strongly influences the distribution of relatively small (radiusa = 150 − 250 nm) astronomical silicates. The unexpected finding is that the heliospheric interface facilitates the penetration ofa = 150 nm particles at small heliocentric distances and, particularly, to the Ulysses orbit (1 − 5 AU). We demonstrate that the deflection of ISD particles in the outer heliosheath is the principal mechanism that causes the effects of the heliospheric interface on the distribution near the Sun. The computations with different heliospheric models show that the distribution near the Sun is sensitive to the plasma parameters in the pristine local interstellar medium. Thus, we demonstrated that being measured near the Sun, the ISD may serve as a new independent diagnostics of the local interstellar medium and the heliospheric boundaries.
The IACOB project
Authors: de Burgos A. , Keszthelyi Z. , Simón-Díaz S. , Urbaneja M. A.
Published: June 2024

The properties of blue supergiants are key for constraining the end of the main sequence (MS) of massive stars. Whether the observed drop in the relative number of fast-rotating stars below ≈21 kK is due to enhanced mass-loss rates at the location of the bistability jump, or the result of the end of the MS is still debated. Here, we combine newly derived estimates of photospheric and wind parameters with Gaia distances and wind terminal velocities from the literature to obtain upper limits on the mass-loss rates for a sample of 116 Galactic luminous blue supergiants. The parameter space covered by the sample ranges between 35–15 kK in Teff and 4.8–5.8 dex in log(L/L⊙). Our results show no increase in the mass-loss rates over the bistability jump. Therefore, we argue that the drop in rotational velocities cannot be explained by enhanced mass loss. Since a large jump in the mass-loss rates is commonly included in evolutionary models, we suggest an urgent revision of the default prescriptions currently in use.
Preface
Authors: Abdullozoda Ramazon , Gibadullin Arthur
Published: June 2024

Within the framework of the presented material, the results of the conducted III International Conference on Agriculture, Earth Remote Sensing and Environment (RSE-III-2024).
Poisonous and harmful plants of pastures in the Kyzylkum desert (Uzbekistan)
Authors: Shomurodov Habibullo , Khayitov Rizamat , Abduraimov Ozodbek , Maxmudov Azizbek , Abduraimov Azizbek
Published: June 2024

The paper studied poisonous and harmful plants that were distributed in Kyzylkum desert condition (Uzbekistan). The research was conducted over the years 2012-2024. The forage flora of Kyzylkum consists of 908 species of vascular plants belonging to 345 genera and 68 families. During the research, 34 families, 73 poisonous plants belonging to 55 genus and 6 families, 39 harmful plants belonging to 13 genera were identified. The vast majority of poisonous and harmful plants are xerophytes. The analysis of poisonous plants of the studied territory in relation to soil moisture showed that the vast majority of them belong to xerophytes, which confirms the arid nature of the pastoral flora of Kyzylkum. The dominant positions of annual plants in the forage flora of the study area have been revealed, which are an alarming indicator of increasing anthropogenic pressure on pasture vegetation. The colossal role of haze and compound flowers in the pasture vegetation of Central Asia has been established and the expediency of separating them into separate groups according to economic relations has been proved.
Comprehensive assessment of the state of the environment in rural and urban areas
Authors: Chernysheva Natalya , Pastukhov Vladislav , Frantseva Tatiana , Sukhomlinova Alexandra , Kolesnikova Irina
Published: June 2024

The article examines the comfort of the environment in rural and urban areas. To assess the level of environmental comfort, methods were used to determine the degree of greening of populated areas, the state of tree plantations within green public areas, the aggressiveness of the visual environment and the quality index of the urban environment. Based on the results of the research, the comfort of the environment in rural and urban areas was compared and conclusions were drawn.
The effect of bacterial products and mineral fertilizers on growth and productivity of Brassica juncea Czern
Authors: Lebedev Vitaliy , Kondrat Sofya , Uraev Grigorii , Khuaz Svetlana , Datkhuzheva Ruzana
Published: June 2024

The paper reports the results of field experiments that analyzed changes in growth indicators and productivity of Sarepta mustard (Brassica juncea Czern.) of the Start variety (k-4259) in response to inoculation and increasing doses of mineral nitrogen. Morphometric parameters and productivity of dry mass were measured during the stage of harvesting maturity, i.e., the full flowering stage. The seeds were inoculated with the following bacterial products: Agrofil (Agrobacterium radiobacter, strain 10), Mizorin (Arthrobacter mysorens, strain 7), Mobilin (Pseudomonas fluorescens, strain PG-5), and Flavobakterin (Flavobacterium sp., strain 30). The amount of nitrogen ranged from N30 to N120. It was enhanced with the application of PK at the rate of 60 kg/ha. The experiments showed that the application of bacterial products and increasing doses of mineral nitrogen has a stimulating effect on plants. The fertilizer formulation N120P60K60 and rhizobacteria strains Flavobacterium sp., strain 30, and Pseudomonas fluorescens, strain PG-5, proved to be the most effective. The obtained data were roughly consistent with the application of N90 and N120. The use of mineral fertilizers resulted in the highest productivity of dry shoot mass.
Reduction of vanadium-titanium magnetite concentrate composite biomass briquette by pure hydrogen under microwave field and separation of titanium and iron
Authors: Tong Shuai , Ai Liqun , Hong Lukuo , Yuan Zhipeng , Zhang Shuai
Published: June 2024

In this study, a new method of microwave-hydrogen synergistic reduction of vanadium-titanium magnetite (VTM) briquette/VTM composite biomass briquette were developed to carry out isothermal experiment. The results showed that under the experimental conditions, excessive biomass would open the channel for gas diffusion and participate in the reduction reaction, but it would weaken the hydrogen reduction to some extent. After grinding the reduction product of VTM composite biomass briquette for 40 min, internal cracks and fragmentation were more likely to occur. After magnetic separation, titanium and iron can be effectively separated, and the nonmagnetic substance is mainly Fe2TiO4 phase.
Das Duo ist in Wahrheit ein Orchester – Nierenerkrankungen im
Zusammenspiel mit den Organsystemen
Authors: Rudat Rüdiger
Published: June 2024

Störungen eines Organs oder Organsystems haben immer auch Auswirkungen auf andere
Organsysteme. Dieser Artikel beschreibt das vielfach ineinandergreifende
Zusammenspiel der Nieren mit anderen Organsystemen wie Herz, Lunge, Leber und
Schilddrüse. Wie hängen diese physiologisch und pathogenetisch voneinander ab
und welche Schlussfolgerungen kann und sollte man für die Therapie daraus
schließen?
Inkontinenz bei der Hündin – ein homöopathischer
Fallbericht
Authors: Magg Monika
Published: June 2024

Vorgestellt wird eine kastrierte Deutsche Pinscher-Hündin mit Inkontinenz, die
bereits vor der Kastration auftrat. Eine zweite Repertorisation, die sich auf
die Blasensymptome konzentrierte, führte schließlich zum passenden Mittel.
Stressbedingte Gastroenteritis bei einem Labrador – ein
Fallbericht
Authors: Rodenbücher Anna Lena
Published: June 2024

Durchfall aufgrund von psychischem Stress? Wie man sich dieser Diagnose nähert
und warum eine ganzheitliche Sicht sinnvoll und wichtig ist, zeigt der folgende
Fallbericht.
Stationäre psychosomatisch-psychotherapeutische Rehabilitation und
ambulante Richtlinienpsychotherapie – Ergebnisse einer
versorgungsepidemiologischen Untersuchung
Authors: Linden Michael , Schymainski David , Solvie Julia , Rose Matthias
Published: June 2024

Hintergrund Die ambulante Richtlinienpsychotherapie stellt qualitativ und
quantitativ eine wichtige Behandlungssäule für Menschen mit psychischen
Störungen dar. Ergänzend stehen stationäre Einrichtungen zur Verfügung. Von
besonderer Relevanz und Häufigkeit sind diesbezüglich psychosomatische
Rehabilitationskliniken. Es fehlen jedoch Daten, zum Zusammenspiel zwischen
ambulanter und stationärer psychotherapeutischer Behandlung, d. h. in wie vielen
Fällen ambulanter Psychotherapiepatienten eine stationäre
psychosomatisch-psychotherapeutische Behandlung stattgefunden hat oder indiziert
wäre und bei welchen Krankheitszuständen.

Methode 131 niedergelassene Psychologische Psychotherapeuten und
Psychotherapeutinnen wurden im Rahmen eines Interviews zu insgesamt 322
Behandlungsfällen mit Blick auf die laufende Behandlung, vorangegangene
Reha-Maßnahmen und eine aktuelle Reha-Indikation befragt.

Ergebnis Nahezu 100% der Psychotherapiepatienten litten unter jahrelangen
psychischen Störungen und bei mehr als der Hälfte der Patienten lagen besondere
berufliche Problemlagen vor, was als Indikationsmerkmal für eine
psychosomatische Rehabilitation angesehen wird. 28% waren bereits in einer
Rehabilitationsmaßnahme, bei weiteren 28% wurde eine solche als indiziert
angesehen. Ein Vergleich von Patienten mit stattgehabten Reha-Maßnahmen,
aktueller Reha-Indikation und ohne Reha-Indikation zeigte, dass die beden
Gruppen der Rehapatienten älter waren, einen geringeren Bildungsstand hatten,
eine höhere Symptomschwere, einen problematischeren Behandlungsverlauf, eine
schlechtere Behandlungsprognose, einen höheren Grad allgemeiner sowie
beruflicher Teilhabeeinschränkungen und einen höheren Bedarf an
sozialmedizinischen Hilfestellungen.

Diskussion Die Daten der vorliegenden Untersuchung zeigen, dass viele
Patienten von Psychotherapeuten unter chronischen und teilhabebeeinträchtigenden
Erkrankungen leiden, bereits in psychosomatischer Rehabilitation waren oder
dorthin eingewiesen werden sollten. Richtlinienpsychotherapeuten sind daher
wichtige Kooperationspartner der stationären
psychosomatisch-psychotherapeutischen Rehabilitation, was sowohl den Reha-Zugang
wie die Reha-Nachsorge betrifft. Eine Aufgabe der Sozialversicherungsträger
sollte sein, die Voraussetzungen für eine gute sektorenübergreifende Kooperation
zu schaffen. Bei der hohen Zahl der Fälle wäre auch die Indikationsstellung für
eine stationäre psychosomatische Rehabilitation zu präzisieren.
Gefäßchirurgische Langzeitergebnisse – Vergleich orthotoper und extraanatomischer Rekonstruktionen bei unilateralen Beckenachsenverschlüssen über 10 Jahre
Authors: Barth Udo , Tautenhahn Jörg , Klinsmann Philipp , Meyer Frank , Halloul Zuhir
Published: June 2024

Bei der pAVK sind zumeist mehrere Gefäßregionen betroffen, die Beckenachse in 35% der Fälle. Zur Rekanalisation sind interventionell-radiologische/endovaskuläre bzw. Hybrideingriffe etabliert, sodass Bypassverfahren zwar zunehmend in den Hintergrund treten, jedoch nicht an Bedeutung verlieren.

Untersuchung unilateraler Beckenarterienverschlüsse (Einschlusskriterium), die entweder durch Implantation eines orthotopen oder extraanatomischen Bypasses (oBP/eaBP) saniert wurden.

Über einen definierten Zeitraum wurden im Vergleich der Rekonstruktionsverfahren Offenheitsrate, Komplikationen (Häufigkeit, Art, Schwere) zur Charakterisierung von Morbidität, Letalität und Ausmaß der klinischen Verbesserung nach BP-Implantation im Rahmen einer klinisch-systematischen, unizentrischen Beobachtungsstudie (Design) analysiert. Die Erstellung der Studienmethode erfolgte nicht explizit anhand der STROBE-Kriterien, entsprechen diesen aber im Wesentlichen.

Über 10 Jahre wurden 122 pAVK-Patienten (50% im Stadium IIb–Stadium III und IV paritätisch verteilt; Durchschnittsalter: 63 [Streubreite: 44–87] Jahre; mehrheitlich ASA III) eingeschlossen bei ebenso vielen Rekonstruktionen: 71 Patienten erhielten einen eaBP („Cross-over“), 51 Patienten einen iliacofemoralen (orthotopen – oBP) Bypass (kein signifikanter Unterschied hinsichtlich Häufigkeit noch Anzahl der Risikofaktoren pro Patient).

Der oBP ist dem eaBP bez. der Analyseparameter Offenheits-, Komplikationsrate sowie Letalität nicht überlegen. Des Weiteren muss die extraanatomische Revaskularisation nicht allein dem Polymorbiden vorbehalten bleiben.
Smart scanning: automatic detection of superficially located lymph nodes using ultrasound – initial results
Authors: Rink Maximilian , Künzel Julian , Stroszczynski Christian , Jung Friedrich , Jung Ernst Michael
Published: June 2024

Over the last few years, there has been an increasing focus on integrating artificial intelligence (AI) into existing imaging systems. This also applies to ultrasound. There are already applications for thyroid and breast lesions that enable AI-assisted sonography directly on the device. However, this is not yet the case for lymph nodes.

The aim was to test whether already established programs for AI-assisted sonography of breast lesions and thyroid nodules are also suitable for identifying and measuring superficial lymph nodes. For this purpose, the two programs were used as a supplement to routine ultrasound examinations of superficial lymph nodes. The accuracy of detection by AI was then evaluated using a previously defined score. If available, a comparison was made with cross-sectional imaging.

The programs that were used are able to adequately detect lymph nodes in the majority of cases (78.6%). Problems were caused in particular by a high proportion of echo-rich fat, blurred differentiation from the surrounding tissues and the occurrence of lymph node conglomerates. The available cross-sectional images did not contradict the classification of the lesion as a lymph node in any case.

In the majority of cases, the tested programs are already able to detect and measure superficial lymph nodes. Further improvement can be expected through specific training of the software. Further developments and studies are required to assess risk of malignancy.
Ketyl Radical Enabled Synthesis of Oxetanes
Authors: Schindler Corinna S. , Gatazka Michael R. , Parikh Seren G. , Rykaczewski Katie A.
Published: June 2024

Oxetanes, 4-membered oxygen-containing heterocycles, were identified to have pharmaceutical applications after the discovery of the chemotherapeutic drug taxol (Paclitaxel) and its analogues. Furthermore, oxetanes have been identified as bioisosteres for several common functional groups and are present in a number of natural products. However, oxetanes are one of the least common oxygen-containing heterocycles in active pharmaceutical ingredients on the market, which can be attributed, in part, due to challenges with their synthesis. Previous strategies rely on nucleophilic substitutions or [2+2]-cycloadditions, but are limited by the stepwise buildup of starting material and limitations in scope resulting from requirements for activated substrates. To address these limitations, we envisioned activating simple carbonyls to their corresponding α-oxy iodides to promote ketyl radical formation. These radicals can then undergo atom-transfer radical addition with alkenes followed by one-pot nucleophilic substitution to produce oxetanes. Herein, we present a proof-of-principle of this strategy in which fluoroalkyl carbonyls are successfully converted into the corresponding fluoroalkyl oxetanes.
Enhanced performance of MoS2/SiO2 field-effect transistors by hexamethyldisilazane (HMDS) encapsulation
Authors: Jana Santu Prasad , Shivangi  , Gupta Suraina , Gupta Anjan K.
Published: June 2024

Scalable methods for improving the performance and stability of a field-effect transistor (FET) based on two-dimensional materials are crucial for its real applications. A scalable method of encapsulating the exfoliated MoS2 on the SiO2/Si substrate by hexamethyldisilazane (HMDS) is explored here for reducing the influence of interface traps and ambient contaminants. This leads to 25 times reduction in trap density, three times decrease in subthreshold swing, three times increase in the peak field-effect mobility, and a drastic reduction in hysteresis. This performance remains nearly the same after several weeks of ambient exposure of the device. This is attributed to the superhydrophobic nature of HMDS and the SiO2 surface hydrophobization by the formation of covalent bonds between the methyl groups of HMDS and silanol groups of SiO2.
Variations of the shock and secondary flow structure in a transonic compressor cascade with outlet back pressure
Authors: Meng Fanjie , Tang Jie , Li Jingyin , Gong Chaoxuan , Guo Penghua
Published: June 2024

The effects of back pressure on the transonic cascade operating state are crucial and can determine the structure of internal shock waves and secondary flows. In this paper, numerical methods validated by experiments were employed to investigate the evolution mechanisms of the inlet flow field, shock structure, secondary flow structure, and cascade performance under different back pressures. Analysis revealed that transonic cascade exhibited unique incidence characteristics in the inlet flow field under both subsonic and supersonic regimes, although these two regimes involved different physical mechanisms. The results revealed that the operating state of the transonic compressor cascade under the unique incidence condition was influenced by the outlet back pressure, and there existed a critical static pressure ratio. The critical static pressure ratio shifted from 1.61 for two-dimensional flow to 1.37 for three-dimensional (3D) flow at M1 = 1.1, due to the corner separation and the characteristics of 3D shocks. The 3D shock structure exhibited a non-uniform distribution along the spanwise direction due to the influence of back pressure and the separated boundary layer. The vortex structures analysis revealed that the secondary flow structure on the sidewalls of the transonic compressor cascade was primarily dominated by corner vortices, whose formation mechanism was related to the interaction between the shock wave and the sidewall boundary layer. Additionally, this interaction also led to the formation of detached shock and lip shock vortex structures. Finally, loss analysis indicated that the wake region of the transonic cascade primarily includes six types of loss, and the total loss of the cascade decreased with the rise in back pressure.
Role of long jumps in Lévy noise-induced multimodality
Authors: Pogorzelec Przemysław , Dybiec Bartłomiej
Published: June 2024

Lévy noise is a paradigmatic noise used to describe out-of-equilibrium systems. Typically, properties of Lévy noise driven systems are very different from their Gaussian white noise driven counterparts. In particular, under action of Lévy noise, stationary states in single-well, super-harmonic, potentials are no longer unimodal. Typically, they are bimodal; however, for fine-tuned potentials, the number of modes can be further increased. The multimodality arises as a consequence of the competition between long displacements induced by the non-equilibrium stochastic driving and action of the deterministic force. Here, we explore robustness of bimodality in the quartic potential under action of the Lévy noise. We explore various scenarios of bounding long jumps and assess their ability to weaken and destroy multimodality. In general, we demonstrate that despite its robustness it is possible to destroy the bimodality, however it requires drastic reduction in the length of noise-induced jumps.
Thermal-induced bandgap broadening phenomenon in copolymer organic semiconductors
Authors: Chang Hengdian , Zhang Jun , Wu Xin , Lin Haonan , Mou Yabin , Wu Zhiyao , Zhou Jia , Qian Haowen , Yao Jiafei , Yang Kemeng , Chen Jing , Li Man , Li Wen , Yi Mingdong , Bai Song , Guo Yufeng
Published: June 2024

This study elucidates the thermal-induced bandgap broadening (TBB) phenomenon in copolymer organic semiconductors (OSCs). From the perspective of device physics, the diketopyrrolopyrrole-based copolymer was employed as the semiconductor layer to fabricate a back-to-back Schottky junction structure. Characterization through the analysis of I–V curves enables the qualitative exploration of the correlation between bandgap and temperature in copolymer OSCs. Then, technology computer-aided design was utilized to explore the influence of thermal-induced bandgap broadening on the back-to-back Schottky I–V curves. Subsequently, the variable temperature UV-VIS-NIR absorption spectra of the copolymer OSCs were analyzed, providing quantitative evidence of the thermal-induced bandgap broadening phenomenon and confirming its recoverability. Through the research of the Schottky junction and absorption spectra, we verified the consistency of the TBB phenomenon in both the electrical and optical bandgaps. From the scanning electron microscope images of the copolymer OSC films, it is found that the thermal-induced bandgap broadening phenomenon is mainly caused by thermal expansion and increased disorder of copolymer molecules. This study highlights a physical phenomenon of copolymer OSCs that is different from most inorganic semiconductors, and such insight offers a theoretical perspective for the application and thermal stability investigation of copolymer devices under high temperature conditions.
Extended dynamic mode decomposition for model reduction in fluid dynamics simulations
Authors: Libero Giulia , Chiofalo Alessia , Ciriello Valentina , Tartakovsky Daniel M.
Published: June 2024

High computational cost and storage/memory requirements of fluid dynamics simulations constrain their usefulness as a predictive tool. Reduced-order models (ROMs) provide a viable solution to this challenge by extracting the key underlying dynamics of a complex system directly from data. We investigate the efficacy and robustness of an extended dynamic mode decomposition (xDMD) algorithm in constructing ROMs of three-dimensional cardiovascular computations. Focusing on the ROMs' accuracy in representation and interpolation, we relate these metrics to the truncation rank of singular value decomposition, which underpins xDMD and other approaches to ROM construction. Our key innovation is to relate the truncation rank to the singular values of the original flow problem. This result establishes a priori guidelines for the xDMD deployment and its likely success as a means of data compression and reconstruction of the system's dynamics from dominant spatiotemporal structures present in the data.
Dependence of EHD instability of plasma/liquid interface on liquid conductivity
Authors: Bordbar Maryam , Hajisharifi Kamal , Mehdian Hassan , Hasanbeigi Ali , Robert Eric
Published: June 2024

Besides numerous experimental reports revealing the characteristic dependence of depression on liquid surfaces induced by impinging plasma beams, and despite its scientific and practical importance, the physical mechanism responsible for this dependency has been missed. In this study, based on the border electrons' role, the water/plasma interfacial dynamics relevant to electrohydrodynamic instability (EHD) have been theoretically modeled, focusing on the characteristic dependence of the EHD growth rate driven by charge mobility mechanisms. The predictions of the growth rates dependent on water conductivity from theory agree well with our observations of faster plasma-filled underwater bubble explosions under lower conductivity conditions, indicating that the model contains the essence of the underlying physics of liquid surface deformation in the presence of plasma.
Probing the optical properties and toxicological profile of zinc tungstate nanorods
Authors: Fang Justin , Hurley Nathaniel , Chien Chia Te , Guo Alan , Khan Tamor A. , Li Mingxing , Cotlet Mircea , Moretti Federico , Bourret Edith , Shifman Sophie , Tsirka Stella E. , Shelly Maya , Wong Stanislaus S.
Published: June 2024

Zinc tungstate is a semiconductor known for its favorable photocatalytic, photoluminescence, and scintillation properties, coupled with its relatively low cost, reduced toxicity, and high stability in biological and catalytic environments. In particular, zinc tungstate evinces scintillation properties, namely the ability to emit visible light upon absorption of energetic radiation such as x rays, which has led to applications not only as radiation detectors but also for biomedical applications involving the delivery of optical light to deep tissue, such as photodynamic therapy and optogenetics. Here, we report on the synthesis of zinc tungstate nanorods generated via an optimized but facile method, which allows for synthetic control over the aspect ratio of the as-synthesized anisotropic motifs via rational variation of the solution pH. We investigate the effect of aspect ratio on their resulting photoluminescent and radioluminescent properties. We further demonstrate the potential of these zinc tungstate nanorods for biomedical applications, such as photodynamic therapy for cancer treatment, by analyzing their toxicological profile within cell lines and neurons.
Structurally simplified GCMO crossbar design for artificial synaptic networks
Authors: Antola Anni , Angervo Ilari , Huhtinen Hannu , Miettinen Mikko , Schulman Alejandro , Paturi Petriina
Published: June 2024

Harnessing the full power of memristors as artificial synapses demands a simple and scalable crossbar architecture enabling their seamless integration into diverse applications. This Letter presents the 3×3 memristor crossbar array configuration featuring a grid of interconnected devices. The composition includes Al as the reactive top electrode connecting the device columns and Gd1−xCaxMnO3 (GCMO, x=0.8) serving as the bottom electrode connecting the device rows as well as the memristive material eliminating the need for additional layers and fabrication steps. Controlled-sized vias through insulating the Al2O3 layer connect the electrodes forming the active interface. The idea is validated with a test sample of 3×3 crossbars with the Au/GCMO/Al structure, Au enabling Ohmic contact to GCMO, with device resistive switching ratios mostly around 102 and yield of over 90%. The devised crossbar structure could provide a highly scalable, yet simple, geometry suitable for synaptic networks.
Achieving n-type doped monoclinic (InxAl1-x)2O3 alloys
Authors: Seacat Sierra , Peelaers Hartwin
Published: June 2024

The monoclinic (In0.25Al0.75)2O3 alloy has been suggested as an ideal material to create monoclinic Ga2O3 heterostructures, as it provides a close lattice match to β-Ga2O3 along with a 1 eV conduction-band offset. Achieving intentional n-type doping in Ga2O3 heterostructures is important for device applications, but this may be difficult due to the high Al content of this alloy. Here, we use density functional theory with a hybrid functional to investigate common donor dopants, in particular, Si, Sn, C, and Ge substituting on cation sites, and H interstitials, in In2O3 and InAlO3. We identify Si as the optimal donor, as it is a shallow donor for In concentrations above 14%. Its formation energy is also low, indicating that these donors will incorporate during growth. For higher In concentrations, Sn (above 33% In) and Ge (above 35% In) are also promising donors, with Sn having comparable formation energies to Si.
Quantum motion of oxygen and hydrogen in water: Atomic and total kinetic energy across melting from neutron scattering measurements
Authors: Romanelli Giovanni , Andreani Carla , Bocedi Alessio , Senesi Roberto
Published: June 2024

We provide a concurrent measurement of the hydrogen and oxygen nuclear kinetic energies in the water molecule across melting at 270 K in the solid phase and 276 K in the liquid phase. Experimental values are obtained by analyzing the neutron Compton profiles of each atomic species in a deep inelastic neutron scattering experiment. The concurrent measurement of the atom kinetic energy of both hydrogen and oxygen allows the estimate of the total kinetic energy per molecule due to the motion of nuclei, specifically 35.3 ± 0.8 and 34.8 ± 0.8 kJ/mol for the solid and liquid phases, respectively. Such a small difference supports results from ab initio simulations and phenomenological models from the literature on the mechanism of competing quantum effects across the phase change. Despite the experimental uncertainties, the results are consistent with the trend from state-of-the-art computer simulations, whereby the atom and molecule kinetic energies in the liquid phase would be slightly lower than in the solid phase. Moreover, the small change of nuclear kinetic energy across melting can be used to simplify the calculation of neutron-related environmental dose in complex locations, such as high altitude or polar neutron radiation research stations where liquid water and ice are both present: for neutron energies between hundreds of meV and tens of keV, the total scattering cross section per molecule in the two phases can be considered the same, with the macroscopic cross section only depending upon the density changes of water near the melting point.
Decrypting the critical point of internal rotation of formaldehyde: A rotational study of the acrolein–formaldehyde complex
Authors: Li Meiyue , Tian Xiao , Du Weiping , Wang Xiujuan , Lei Juncheng , Gao Tianyue , Zou Siyu , Xu Xuefang , Wang Hao , Chen Junhua , Gou Qian
Published: June 2024

The rotational spectrum of an acrolein–formaldehyde complex has been characterized using pulsed jet Fourier transform microwave spectroscopy complemented with quantum chemical calculations. One isomer has been observed in pulsed jets, which is stabilized by a dominant O=C⋯O tetrel bond (n → π* interaction) and a secondary C–H⋯O hydrogen bond. Splittings arising from the internal rotation of formaldehyde around its C2v axis were also observed, from which its V2 barrier was evaluated. It seems that when V2 equals or exceeds 4.61 kJ mol−1, no splitting of the spectral lines of the rotational spectrum was observed. The nature of the non-covalent interactions of the target complex is elucidated through natural bond orbital analysis. These findings contribute to a deeper understanding on the non-covalent interactions within the dimeric complex formed by two aldehydes.
p-block germanenes as a promising electrocatalysts for the oxygen reduction reaction
Authors: Wang Pengju , Xia Weizhi , Liu Nanshu , Pei Wei , Zhou Si , Tu Yusong , Zhao Jijun
Published: June 2024

The oxygen reduction reaction (ORR), a pivotal process in hydrogen fuel cells crucial for enhancing fuel cell performance through suitable catalysts, remains a challenging aspect of development. This study explores the catalytic potential of germanene on Al (111), taking advantage of the successful preparation of stable reconstructed germanene layers on Al (111) and the excellent catalytic performance exhibited by germanium-based nanomaterials. Through first-principles calculations, we demonstrate that the O2 molecule can be effectively activated on both freestanding and supported germanene nanosheets, featuring kinetic barriers of 0.40 and 0.04 eV, respectively. The presence of the Al substrate not only significantly enhances the stability of the reconstructed germanene but also preserves its exceptional ORR catalytic performance. These theoretical findings offer crucial insights into the substrate-mediated modulation of germanene stability and catalytic efficiency, paving the way for the design of stable and efficient ORR catalysts for future applications.
Improved optimization for the neural-network quantum states and tests on the chromium dimer
Authors: Li Xiang , Huang Jia-Cheng , Zhang Guang-Ze , Li Hao-En , Shen Zhu-Ping , Zhao Chen , Li Jun , Hu Han-Shi
Published: June 2024

The advent of Neural-network Quantum States (NQS) has significantly advanced wave function ansatz research, sparking a resurgence in orbital space variational Monte Carlo (VMC) exploration. This work introduces three algorithmic enhancements to reduce computational demands of VMC optimization using NQS: an adaptive learning rate algorithm, constrained optimization, and block optimization. We evaluate the refined algorithm on complex multireference bond stretches of H2O and N2 within the cc-pVDZ basis set and calculate the ground-state energy of the strongly correlated chromium dimer (Cr2) in the Ahlrichs SV basis set. Our results achieve superior accuracy compared to coupled cluster theory at a relatively modest CPU cost. This work demonstrates how to enhance optimization efficiency and robustness using these strategies, opening a new path to optimize large-scale restricted Boltzmann machine-based NQS more effectively and marking a substantial advancement in NQS’s practical quantum chemistry applications.
Multi-parametric magnetic resonance imaging of the prostate in Victoria, Australia; unintended consequences of changing Medicare Benefits Schedule access
Authors: Gordon Patrick , Urquhart Evan , Oad Symrin , Mackenzie Kenneth , Paul Eldho , McCahy Philip
Published: June 2024

Objective To assess whether prostate biopsy rates have altered with the July 2018 change in Australian Medicare Benefits Schedule (MBS) rebates supporting multiparametric magnetic resonance imaging (mpMRI) for diagnosing prostate cancer. Methods Biopsy data (both trans-rectal and trans-perineal) were obtained from the Victorian Agency for Health Information from July 2016 to June 2022. The data were stratified by financial year, age group and hospital type (public vs private). Comparison was made between rates pre and post the mpMRI MBS code change. Results There was an 11.9% increase in the number of biopsies performed per year compared to the pre-MBS change period. There is a significant decreasing trend (P < 0.001–4) in number of biopsies in the 40–49, 50–59 and 60–69-year-old age groups with a significant increasing trend (P < 0.001) in the 70–79 and 80–89-year-old age groups. There was a 32.9% reduction in the mean number of biopsies performed per year in public hospitals, compared with an 18.3% increase in private. Conclusion Contrary to expectations, and proposed funding, there has been an increase in the number of prostate biopsies since MRI became more easily available. This change will put increased pressure on the health budget and the large increase in biopsies in elderly patients was not anticipated when the changes were proposed. A review of the criteria is suggested.
Schoenoplectus californicus (Cyperaceae) amorphous silica contribution to the silicon cycle in pampean shallow lakes: an analysis of spatio-temporal variation and silicon–lignin relations
Authors: De Rito Mara , Borrelli Natalia , Natal Marcela , Fernández Honaine Mariana
Published: June 2024

Context Phytoliths constitute an important source of silicon in terrestrial and aquatic ecosystems. Schoenoplectus californicus (C.A.Mey.) Soják (Cyperaceae) is an important phytolith producer. Aims We investigated the spatio-temporal variation in phytolith content of S. californicus in shallow lakes of the Pampean region, considering biomass and its relation to soil silicon content and lignin content. Methods Calcination techniques were applied to quantify phytoliths. The biomass was estimated by destructive methods. Soil silicon concentration was determined through ultraviolet–visible spectrophotometry by means of the silicomolybdate method. For lignin determination, a fibre analyser and sulfuric acid were used. Key results No significant differences were observed in the spatio-temporal analysis. There were no differences in the biomass estimation and in the phytolith per m2 contribution. Regarding soil silicon content, when the concentration was low, the phytolith production was low. Lignin content remained constant between sites. No correlation was observed between phytolith and lignin content. Conclusions S. californicus is an accumulator of amorphous silica, generating a constant quantity of phytoliths over the years and between sites. The variation in some environmental conditions does not seem to be enough to be reflected in plant silica production. No relation between lignin and silica was found, perhaps due to their different roles in plant structure. Implications The inclusion of other wetlands with more contrasting conditions may reveal the environmental constraints for the amorphous silica production. This study shows the importance of this community as a silicon source, and the implications of its displacement by other communities or urban development.
Are separable words words or phrases?
Authors: Xia Quansheng , Wang Ai
Published: June 2024

Both traditional linguistics and psycholinguistics have extensively explored the issue of the category that
separable words belong to, yet different opinions persist. Building upon previous research, this study selects verb-complement
structures as its focal point. Based on the number of internally insertable elements, these structures are categorized into
verb-complement compounds, verb-complement compact structures, verb-complement loose structures, and verb-complement phrases. The
study compares the processing similarities and differences between the four types of structures with and without inter-component
spacing so that the “disconnected” and “connected” states of the four structures are investigated. Experimental results indicate
that regardless of the insertion of spaces, the reaction times for processing verb-complement compounds, compact structures, and
loose structures are shorter than those for phrases. In the comparison of presence and absence of spaces, compounds and compact
structures exhibit greater consistency, whereas no significant differences are observed between loose structures and phrases. This
suggests that the processing of verb-complement compact structures closely resembles that of words, while the processing of loose
structures embodies characteristics of both compounds and phrases, yet differs from both words and phrases. This study
demonstrates that based on the degree of internal expansion, separable words can be further classified into subcategories,
existing in a transitional state between words and phrases, forming a continuous continuum with compounds and phrases.
Rethinking tokenization
Authors: Yang Jinbiao
Published: June 2024

Tokenization significantly influences language models (LMs)’ performance. This paper traces the evolution of tokenizers from word-level to
subword-level, analyzing how they balance tokens and types to enhance model
adaptability while controlling complexity. Despite subword tokenizers like Byte
Pair Encoding (BPE) overcoming many word tokenizer limitations, they encounter
difficulties in handling non-Latin languages and depend heavily on extensive
training data and computational resources to grasp the nuances of multiword
expressions (MWEs). This article argues that tokenizers, more than mere
technical tools, should drawing inspiration from the cognitive science about
human language processing. This study then introduces the “Principle of Least
Effort” from cognitive science, that humans naturally seek to reduce cognitive
effort, and discusses the benefits of this principle for tokenizer development.
Based on this principle, the paper proposes that the Less-is-Better (LiB) model
could be a new approach for LLM tokenizer. The LiB model can autonomously learn
an integrated vocabulary consisting of subwords, words, and MWEs, which
effectively reduces both the numbers of tokens and types. Comparative
evaluations show that the LiB tokenizer outperforms existing word and BPE
tokenizers, presenting an innovative method for tokenizer development, and
hinting at the possibility of future cognitive science-based tokenizers being
more efficient.