bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous intracranial hypotension: from cerebral venous thrombosis to neurosurgical treatment: a case series experience from a Brazilian tertiary health care center
Authors: Moreira Daniel Gabay , Félix Evandro Penteado Villar , Onishi Franz Jooji , Ferraz Henrique Ballalai , Coradine Tácio Luis Cavalcante , Braga Vinícius Lopes , Oliveira Enedina Maria Lobato de
Published: March 2023

Background Spontaneous intracranial hypotension (SIH) is a secondary cause of headache and an underdiagnosed disease. The clinical presentation can be highly variable. It typically presents with isolated classic orthostatic headache complaints, but patients can develop significant complications such as cerebral venous thrombosis (CVT).

Objective To report 3 cases of SIH diagnosis admitted and treated in a tertiary-level neurology ward.

Methods Review of the medical files of three patients and description of clinical and surgical outcomes.

Results Three female patients with SIH with a mean age of 25.6 ± 10.0 years old. The patients had orthostatic headache, and one of them presented with somnolence and diplopia because of a CVT. Brain magnetic resonance imaging (MRI) ranges from normal findings to classic findings of SIH as pachymeningeal enhancement and downward displacement of the cerebellar tonsils. Spine MRI showed abnormal epidural fluid collections in all cases, and computed tomography (CT) myelography could determine an identifiable cerebrospinal fluid (CSF) leak in only one patient. One patient received a conservative approach, and the other two were submitted to open surgery with laminoplasty. Both of them had uneventful recovery and remission in surgery follow-up.

Conclusion The diagnosis and management of SIH are still a challenge in neurology practice. We highlight in the present study severe cases of incapacitating SIH, complication with CVT, and good outcomes with neurosurgical treatment.
Motor and cognitive outcomes of neonates with low birth weight in Brazil: a systematic review and meta-analysis
Authors: Radaelli Graciane , Leal-Conceição Eduardo , Kalil Neto Felipe , Taurisano Melissa Rogick Guzzi , Majolo Fernanda , Bruzzo Fernanda Thays Konat , Booij Linda , Nunes Magda Lahorgue
Published: March 2023

Background Data on the outcomes of preterm newborns in South American countries are scarce. Given the great effect of low birth weight (LBW) and/or prematurity on children's neurodevelopment, it is extremely necessary to conduct studies on these phenomena in greater depth in more heterogeneous populations such as those ones from countries with limited resources.

Methods We conducted a comprehensive literature search on databases including PubMed, the Cochrane Library, and Web of Science for articles published in Portuguese and English up to March 2021 involving children born and evaluated in Brazil. The analysis of the risk of bias was adapted from the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement and used to evaluate the methodology of the included studies.

Results From the eligible trials, 25 articles were selected for qualitative synthesis, and 5 of those, for quantitative synthesis (meta-analysis). The meta-analyses showed that children born with LBW presented lower scores on motor development when compared with controls (standardized mean difference: −1.15; 95% confidence interval [95%CI]: −1.56–−0.73]; I2: 80%) and also scored lower in terms of cognitive development (standardized mean difference: −0.71; 95% CI: −0.99–−0.44; I2: 67%).

Conclusion The results of the present study reinforce that impaired motor and cognitive functions can be a significant long-term outcome of LBW. The lower the gestational age at delivery, the higher the risk of impairment in those domains. The study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) database under number CRD42019112403.
Prognosis of MGMT-Positive Gene in Patients with Brain Tumors of Grade III and Grade IV
Authors: Rajendra Ishitaa , Dhal Shikha , Goyal Sumit , Tyagi Surabhi , Sharma B. S. , Yadav Ajay , Yadav Dinesh
Published: March 2023

Objective To evaluate MGMT gene positivity is associated with better survival in patients diagnosed with brain tumor World Health Organization (WHO) grades III and IV

Material and Methods Single-institute restrospective study. A total of 80 patients were enrolled, all underwent surgery either total or subtotal excision of the tumor and MGMT gene testing on tumor tissue by RT-PCR. All received adjuvant radiation (60 Gy/30 fractions, 5 fractions/week) with concurrent temozolomide (75 mg/m2), followed by 12 cycles of adjuvant temozolomide (150 mg/m2 1st cycle followed by 200 mg/m2) with regular follow-up.

Results A total of 80 patients, 75 underwent subtotal excision, 27 were WHO grade III vs. 48 WHO grade IV. Five underwent total excision 1 was WHO grade III vs. 4 WHO grade IV. The median PFS and OS in five patients in total excision in grade III patient was 9.0 and 20 compared with Grade IV, where the median PFS and OS was 8.8 and 17.8 months. Out of 75 patients in the subtotal group median PFS and OS, respectively, in Grade III group was 9.1 and 19.3 and, WHO grade IV with median PFS of 8.8 and OS of 18.8.

Conclusion MGMT gene positivity is a prognostic factor in grade III and IV brain tumor.
Prevalence, Habit Pattern, and Awareness on Harmful Effects of Tobacco/Areca Nut Use among Patients Visiting a Tertiary Care Center in Sri Lanka
Authors: Subasinghe S.P. Kalpana Jeewanthi , Hettiarachchi Pilana Vithanage Kalani Shihanika , Jayasinghe Ruwan Duminda
Published: March 2023

Background The carcinogenicity of tobacco and areca nut is well established worldwide. Areca nut is the fourth most common psychoactive substance identified recently. The effects of areca nut on the autonomic nervous system make the users dependent on the habit which has been an emerging health issue among Sri Lankan adults and adolescents. This study aimed to evaluate the prevalence and patterns of these risk habits among the patients attending a tertiary care center in Sri Lanka, and their awareness of the harmful effects of the habit.

Method A hospital-based cross-sectional study was conducted among 512 patients using an interviewer-administered questionnaire.

Results The sample consisted of 167 (33%) tobacco consumers. The average age of the initiation of tobacco consumption was 23.66 years (standard deviation ± 8.04). Age (p = 0.001), gender (p = 0.001), income (p = 0.005), and educational level (p = 0.001) are significantly associated with tobacco consumption. There is a strong likelihood for tobacco consumers to consume areca nut (odds ratio [OR] 30.58, 95% confidence interval [CI] 17.05–54.88) and alcohol (OR 11.16, 95% CI 6.91–17.98) at any stage in their lives. The majority of the tobacco consumers (61%) were smokeless tobacco users. Areca nut consumers are 0.44 times more likely to know its carcinogenic effects than nonconsumers (95% CI 0.28–0.69). Tobacco consumers are more likely to be aware of the harmful effects of tobacco consumption than nonconsumers (OR 1.11, 95% CI 0.45–2.74). Sixty percent have made at least one attempt to quit the habit. Sixty-two percent of the unsuccessful quitters reported the reason as “addiction.”

Conclusion Prevalence of smokeless tobacco consumption prevails at a high level among Sri Lankans. Tobacco and areca nut users are more likely to be aware of its harmful effects than the nonconsumers but unable to quit the habit due to the psychoactive properties of tobacco and areca nut.
Atraumatic Bone Marrow Edema Involving the Epiphyses
Authors: Woertler Klaus , Neumann Jan
Published: March 2023

Bone marrow edema (BME)-like signal intensity involving the epiphyses of tubular bones represents a frequent magnetic resonance imaging finding associated with a wide spectrum of bone and joint disorders. It is important to distinguish this finding from cellular infiltration of bone marrow and to be aware of the differential diagnosis of underlying causes. With a general focus on the adult musculoskeletal system, this article reviews the pathophysiology, clinical presentation, histopathology, and imaging findings of nontraumatic conditions associated with epiphyseal BME-like signal intensity: transient bone marrow edema syndrome, subchondral insufficiency fracture, avascular necrosis, osteoarthritis, arthritis, and bone neoplasms.
Magnetic Resonance Imaging of Accelerated Bone Remodeling
Authors: Vande Berg Bruno C. , Mourad Charbel , Omoumi Patrick , Malghem Jacques
Published: March 2023

A regional acceleration of bone remodeling may possibly follow biomechanical insults to the bone. This review assesses the literature and clinical arguments supporting the hypothetical association between accelerated bone remodeling and bone marrow edema (BME)-like signal intensity on magnetic resonance imaging. BME-like signal is defined as a confluent ill-delimited area of bone marrow with a moderate decrease in signal intensity on fat-sensitive sequences and a high signal intensity on fat-suppressed fluid-sensitive sequences. In addition to this confluent pattern, a linear subcortical pattern and a patchy disseminated pattern have also been recognized on fat-suppressed fluid-sensitive sequences. These particular BME-like patterns may remain occult on T1-weighted spin-echo images. We hypothesize that these BME-like patterns, with particular characteristics in terms of distribution and signal, are associated with accelerated bone remodeling. Limitations in recognizing these BME-like patterns are also discussed.
Implementation of Wideband Acoustic Immittance in Clinical Practice: Relationships among Audiologic and Otologic Findings
Authors: Sanford Chris A. , Brockett Jeff E. , Aithal Venkatesh , AlMakadma Hammam
Published: March 2023

A number of studies have produced normative and developmental data and examples of wideband acoustic immittance (WAI) obtained in ears with pathologies and or dysfunction. However, incorporation of this tool into clinical audiology and otolaryngology practice has been slower than expected, potentially due to challenges with interpretation, integration into existing test batteries, and confidence in practical application. This article presents information aimed at helping clinicians increase their confidence in using this new tool by becoming more familiar and making connections with the ways that WAI outcomes both align with and add to standard immittance, audiometric and otologic diagnostic test outcomes. This article presents several case studies to demonstrate the use of WAI in realistic clinical settings. Each case presents a brief background, case history, audiologic/otologic findings, and initial recommendations, followed by a discussion on how the inclusion of WAI test outcomes aids in diagnostic decisions. The overall aim of this work is to identify the relationships among different diagnostic test outcomes, to demonstrate basic WAI interpretation principles, and encourage the reader to engage with this diagnostic tool in clinical practice.
Solvent effect of water on the UV-B absorption of plant sunscreen agents
Authors: Hu Min , Ye Ke , Jiang Jun , Zhang Guozhen
Published: March 2023

These authors contributed equally to this work. UV-B (280-320 nm) sunscreening is crucial for lives on Earth. Examining the role of surrounding of UV-B screening molecules can help us better understand UV-B absorption. Water is ubiquitous in cells as the solvent, but its impacts on UV-B absorption of sunscreen agents are underexplored. Herein, we report a first-principle study on UV-B absorption of sinapate malate (SM) and relevant molecular species, with a focus on the solvent effect of water. The capability of UV-B screening by anions of SM, the proposed species for actual sunscreening, is shaped by water. Both the implicit water providing the dielectric environment of solvation and the explicit water molecules forming hydrogen bonding to SM anion can appreciably alter the nature of transition orbitals responsible to the UV-B absorption of the anion. Finally, we find the molecular dipole moment of an organic UV-B screening agent can be an indicator of its UV-B screening sensitivity to the surrounding water. Our work may serve as a starting point of developing new water-soluble UV-B screening agent.
Effects of ambient air on functional stability of single-molecule spin logic gate
Authors: Zhang Guang-Ping , Sun Yun-Zhe , Shi Ni-Ping , Yu Chao-Jie , Kong Ya-Qi , Huang Hui , Wang Zi-Qun
Published: March 2023

Single-molecule spin logic gates provide fundamental functions and are of importance in the field of molecular spintronics. Here, by using the firstprinciples method, the effects of ambient gas molecules (CO2, O2, N2, or H2O) on the functional stability of the investigated single-molecule spin logic gate consisting of two serially connected cobalt dibenzotetraaza[14]annulene (CoDBTAA) molecules between single-walled carbon nanotubes (SWCNTs) electrodes, have been theoretically investigated. The calculated results suggest that the investigated spin logic gate can realize AND, NOR, or XNOR logic functions depending on the definition of the input and output signals. It is found that these logic functions are not affected by CO2 adsorption. On the contrary, these logic functions are no longer retained upon O2, N2, or H2O adsorption. Further analysis reveals that the interaction between the CoDBTAA molecule and the CO2 adsorbate is very weak while it is strong for O2, N2, or H2O molecules. Therefore, the electronic states of the logic gate around Fermi energy (EF) are almost unchanged for CO2 adsorption. While the adsorption of O2, N2, or H2O obviously modifies the electronic states around EF. The strong interaction between CoDBTAA and these three gas adsorbates drives the conductive electronic states to move far away from EF, resulting in the blocking of both spin-up and spin-down currents and further voiding the logic functions. This work suggests that ambient air has an important effect on the functional stability of single-molecule devices and should be carefully evaluated in the future design of functional single-molecule devices.
Structural and thermal properties of Eu2Ga11Sn35
Authors: Gunatilleke Wilarachchige D. C. B. , Zhang Mingjian , Wong-Ng Winnie , Zavalij Peter , Chen Yu-Sheng , Nolas George S.
Published: March 2023

Clathrates have been reported to form in a variety of different structure types; however, inorganic clathrate-I materials with a low-cation concentration have yet to be investigated. Furthermore, tin-based compositions have been much less investigated as compared to silicon or germanium analogs. We report the temperature-dependent structural and thermal properties of single-crystal Eu2Ga11Sn35 revealing the effect of structure and composition on the thermal properties of this low-cation clathrate-I material. Specifically, low-temperature heat capacity, thermal conductivity, and synchrotron single-crystal x-ray diffraction reveal a departure from Debye-like behavior, a glass-like phonon mean-free path for this crystalline material, and a relatively large Grüneisen parameter due to the dominance of low-frequency Einstein modes. Our analyses indicate thermal properties that are a direct result of the structure and composition of this clathrate-I material.
Analysis of axial waves in viscoelastic complex structural-acoustic systems: Theory and experiment
Authors: Rojas J. A. , Morales A. , Gutiérrez L. , Otero J. A. , Carrillo E. A. , Monsivais G. , Flores J.
Published: March 2023

An experimental and theoretical study of the spectral response of coupled viscoelastic bars subject to axial oscillations is performed. Novel closed formulas for the envelope function and its width are derived. These formulas explicitly show the role played by energy dissipation. They show that the internal friction does not affect the width of the envelope of the individual resonances. The formulation is based on the equations of classical mechanics combined with Voigt’s viscoelastic model. The systems studied consist of a sequence of one, two, or three coupled bars, with their central axes collinear. One of the bars is assumed to be much longer than the others. We discuss the connection between our results and the concept of the strength function phenomenon discovered for the first time in nuclear physics. Our formulation is an alternative and exact approach to the approximated studies based on the fuzzy structure theory that has been used by other authors to describe systems consisting of coupled bars. The analytical expressions describe the measurements in the laboratory very well.
Electron-beam lithography of nanostructures at the tips of scanning probe cantilevers
Authors: Forrer L. , Kamber A. , Knoll A. , Poggio M. , Braakman F. R.
Published: March 2023

We developed a process to fabricate nanoscale metallic gate electrodes on scanning probe cantilevers, including on the irregular surface of protruding cantilever tips. The process includes a floating-layer technique to coat the cantilevers in an electron-beam resist. We demonstrate gate definition through a lift-off process and through an etching process. The cantilevers maintain a high force sensitivity after undergoing the patterning process. Our method allows the patterning of nanoscale devices on fragile scanning probes, extending their functionality as sensors.
Application of spectral-domain optical coherence tomography technique to in-process measure hole depth during femtosecond laser drilling in different alloys
Authors: Xu P. , Yu Y. , Liu R. J. , Zha K. , Zhou L. , Liu Y. T. , Xu Z.
Published: March 2023

In this paper, a real-time diagnostic based on the spectral-domain optical coherence technique has been developed to measure the hole depth during femtosecond laser drilling. This diagnostic borrows the idea of a fiber interferometer, and the hole is integrated as a part of the sample arm. By means of investigating the interference fringes detected by the line camera, the hole depth can be extracted. This diagnostic utilizes a broadband small-volume super-luminescent diode as the coherent light source, which has a central wavelength of 833 nm and a full width at half maximum of 24 nm. It has a temporal resolution of 50 µs and a maximal theoretic depth resolution of 12.8 µm. Three kinds of metal samples have been tested, confirming the ability of depth measurement. Copper has been proven to have the best-normalized reflectivity during drilling compared with aluminum alloy and stainless steel.
Theoretical analysis of photoacoustic effects in a multilayered skin tissue model
Authors: Cao Na , Li Yanhua , Zhang Ruoyu , Liu Shubin , Xiong Yuping , Cao Hui
Published: March 2023

Due to its noninvasiveness, high resolution, and high sensitivity, photoacoustic imaging has developed rapidly in the field of biomedicine. However, research on dermatosis detection by photoacoustic imaging is still lacking. In this paper, the skin is modeled as a multilayer planar medium based on the non-homogeneous, complex layered structure of the skin tissue. Then, the analytical expression for the photoacoustic signal of multilayer skin tissue was derived under the assumption that the thermal and optical parameters of the skin tissue do not vary with temperature. The expression not only considers the influence of optical, thermal, and mechanical parameters of the tissue on the photoacoustic signal but also, for the first time, the influence of the number of skin layers on the photoacoustic signal. The analytical expression of the photoacoustic signal containing the number of skin layers is also given. The numerical simulation results show that the difference between the photoacoustic signal of the seven-layer skin model and the single-layer skin model is 15.206 × 10−6 MPa when ω = 3.5 MHz and μa = 2.70 cm−1. Therefore, the increase in the number of model layers enhances the amplitude of its photoacoustic signal. This work provides a comprehensive study of photoacoustic mechanisms in dermatosis tissues and establishes a theoretical foundation for the application of photoacoustic imaging detection technology in the diagnosis and treatment of dermatosis, which may improve treatment plans.
Numerical study on vortex-induced vibrations of a flexible cylinder subjected to multi-directional flows
Authors: Qu Yang , Wang Piguang , Fu Shixiao , Zhao Mi
Published: March 2023

Vortex-induced vibrations (VIVs) of a flexible cylinder subjected to multi-directional flows have been studied based on a wake oscillator model. The multi-directional flow comprises two slabs of flows in different directions, with each slab having a uniform uni-directional profile. The dynamics of the flexible cylinder is described based on the linear Euler–Bernoulli beam theory, and a wake oscillator model is uniformly distributed along the cylinder to model the hydrodynamic force acting on it. The dynamics of the coupled system has been solved numerically using the finite element method, and simulations have been conducted with the cylinder subjected to multi-directional flows with different angles between the two slabs. A large number of different initial conditions have been applied, and more than one steady-state response has been captured. The steady-state responses exhibit two different patterns: one is characterized by two waves traveling in opposite directions, while the other is dominated by a single traveling wave. The cross-flow VIV primarily occurs in the local cross-flow direction, and a transition of its vibrating direction happens at the interface of the two flows. Such transition is not observed in the inline VIV, and significant vibrations at the double frequency appear in both local cross-flow and inline directions. Energy analysis shows that this transition is boosted by a specific energy transfer pattern between the structure and the flow, which excites the vibration of the cylinder in some directions while damps it in others.
Structures and properties of uranium–niobium intermetallic compounds under high pressure: A first principles study
Authors: Bao Nanyun , Tong Qunchao , Guo Fangyu , Zhang Shen , Kang Dongdong , Akinpelu Akinwumi , Lv Jian , Yao Yansun , Dai Jiayu
Published: March 2023

Metallic uranium-based alloys, with d-transition metals such as Nb, Mo, and Zr, are promising candidates for actinide fuel. For this purpose, their behaviors under changing physical stimuli need to be understood. Here, we systematically investigate U–Nb intermetallic compounds and predict new compound formations under different pressures using the first-principles swarm-intelligence structure searching method. Two new compounds (U1Nb6 and U2Nb1) were identified to be thermodynamically stable at ambient and high pressures. U1Nb6 has a triclinic symmetry that is stable in the pressure range of 0–200 GPa, while U2Nb1 has a hexagonal closely packed structure at low pressure and transforms to a simple hexagonal lattice at 20 GPa. Other compounds, particularly U-rich ones (U3Nb1, U4Nb1, U5Nb1, and U6Nb1), are found metastable at ambient and high pressures, and all have orthorhombic structures. The structural, vibrational, electronic, and mechanical properties of predicted U-rich compounds were thoroughly studied using density-functional theory. The results of phonon spectra and elastic constant show that the predicted new structures are dynamically and mechanically stable in the corresponding pressure range. Also, these newly identified U-rich compounds exhibit strong composition dependence, and the pressure-induced enhancements of structural stability and mechanical performances are evident. These findings shall enrich the understanding of U-based alloys and serve as meaningful predictions for experimental research in the future.
Carbon nanotubes/polyaniline as hydrogen gas sensor: Optical bandgap, micro-morphology, and skin depth studies
Authors: Bafandeh Nastaran , Solaymani Shahram , Sabbaghzadeh Jamshid , Dejam Laya , Ghaderi Atefeh , Țălu Ștefan , Shafiekhani Azizollah , Sari Amir Hossein
Published: March 2023

In this study, multiwall carbon nanotubes (MWCNTs)/polyaniline nanocomposites deposited on ITO coated glass as substrate by the spin-coating technique were applied to the investigation of the effect of different contents of MWCNTs on the optical and electrical properties of polyaniline. Micrographs from an atomic force microscope were taken to analyze the 3-D microtexture parameters of surface texture factors and fractal dimension. By using optical spectroscopy of samples with different concentrations of MWNCTs in visible and ultraviolet regions, the transmission variations vs photon wavelength, optical bandgap, absorption coefficient, and skin depth were studied. The variation in the resistance of nanocomposite films exposed to 0.4 %vol of H2 gas at room temperature was monitored, and the results indicated that the sensitivity and responsibility of the composites increased with an increase in the MWCNT amount.
Interaction between the oil droplet in water and wetted wall: Force model and motion law
Authors: Rong Feng , He Limin , Lǚ Yuling , Lu Xiaolei
Published: March 2023

To investigate the force model and motion law of oil droplets in water near the wetted wall, oil droplets with R1 = 0.29–0.62 mm and oil films with R2 = 1–6 mm are solved numerically. In addition to buoyancy, flow resistance, and added mass force, the film-induced force triggered by the wetted wall constraint is also introduced into the force model. The drainage process is described using the Stokes–Reynolds equation, and the Young–Laplace equation is used to calculate the pressure within the water film. The results show that the force model can be coupled with the Stokes–Reynolds–Young–Laplace model equation to better describe the drainage dynamics near the wetted wall. The pressure distribution law is closely related to the shape of the water film, especially when the oil–water interface is in the shape of a dimple, which can lead to the formation of negative pressure zones within the water film. The maximum pressure first grows in an exponential, then logarithmic pattern and eventually approaches the equivalent Laplace pressure. Around the critical size, the direction of the film-induced force changes and the form of action switches between driving and drag forces. The film-induced force's dominant effect is strongest when the curvature radius of the oil film is comparable to the droplet size.
Torsional mode magnetostrictive patch transducer with TPSMs for liquid-filled pipes inspection
Authors: Cao Shuang , Li Ming ming , Wang Qian , Weng Ling , Huang Wen mei
Published: March 2023

T (0,1) mode guided waves have no axial or radial vibration displacement. Therefore, the energy leakage is small in liquid-filled pipes, which is suitable for detecting the axial defects of the liquid-filled pipes. Fe–Co materials with high magnetostriction coefficient is fabricated. Its magnetic properties are tested. The size and distribution of static magnetic fields generated by different permanent magnets are verified by simulation. A new torsional mode guided wave magnetostrictive patch transducer with tile-shaped permanent magnets for defect detection of the liquid-filled pipes is proposed. The detection effect of the transducer on the liquid-filled pipes under different pressures is tested through experiments. The proposed transducer consists of four tile-shaped permanent magnets, eight triangular yokes, a coil, and two magnetostrictive patches. Four groups of tile permanent magnets are symmetrically distributed around the patch according to the polarity. Magnetic yokes are installed at both ends of each group of tile permanent magnets. The experiment verified that the magnetostrictive patch transducer realize the excitation and reception of guided wave signals in the magnetostrictive patches. The amplitude and signal-to-noise ratio of echo signals is improved. The position of pipe defects is determined according to the propagation time of guided wave. The influence of different pressures in the liquid-filled pipes on the amplitude of guided wave is verified.
Resource partitioning between Caucasian chamois and domestic sheep in mountain pastures of the eastern Caucasus, Dagestan, Russia
Authors: Magomedov Magomedrasul , Babaev Elmar
Published: March 2023

Feeding and spatial distribution of Caucasian chamois and domestic sheep were studied in the eastern Caucasus. Trophic analysis showed that the chamois diet consisted of 12 herbaceous species and 21 for sheep. Chamois selected forbs and fabaceous species, whereas sheep foraged less selectively. The trophic niche breadth (averaged) of sheep was significantly greater (9.75) than that of chamois (4.33). Trophic niche overlap reached 86% in spring and 56.6% in autumn, and the summer spatial niche breadth of chamois was lower (0.83) than that of sheep (1.46). The spatial niche overlapping of both species was low (17%). Five environmental parameters made the highest contributions to interspecific differences. Chamois habitats in spring were characterised by a lower total phytomass level and higher-calorie herbaceous group biomass (forbs, fabaceous) than in sheep-grazing areas, whereas in autumn, the high-calorie herbaceous-group biomass was higher in chamois habitats than in sheep pastures. We deduce that the chamois spatial pattern is a potential response to sheep presence; chamois moves to difficult-to-reach habitats. Therefore, ecological segregation could be potentially expected due to divergence along the spatial axis of the ecological niche.
Simulations of light distribution on new instrumented baffles surrounding Virgo end mirrors
Authors: Macquet A , Andrés-Carcasona M , Martínez M , Mir Ll M , Romero-Rodríguez A , Yamamoto H
Published: March 2023

As part of the second phase of Advanced Virgo upgrade program, instrumented baffles are being constructed to be installed around the end mirrors (EMs) in the main arms, in continuation of what has been implemented for the input mode cleaner EM during phase I. These baffles will be equipped with photosensors, allowing for real-time monitoring of the stray light around the mirrors. In this paper, we present optical simulations of the light distribution in the detector’s main cavities to assess the ability of the sensors to effectively monitor misalignment and defects on the mirrors’ surface and to play a role in the pre-alignment of the interferometer.
Residual gas damping noise in constrained volume in space-borne gravitational wave detection
Authors: Mao Jiao-Jiao , Tan Yu-Jie , Liu Jian-Ping , Yang Shan-Qing , Luo Jie , Shao Cheng-Gang , Zhou Ze-Bing
Published: March 2023

The residual gas damping in the enclosure surrounding a free-fall test mass is an important limiting factor for the sensitivity of some space detection missions. We present a constrained volume damping model for space-borne gravitational wave detection, which depends on the escape time needed for a molecule to diffuse out of the gap between two adjacent surfaces. Using a completely inelastic molecular collision prediction, we calculate the escape times in the two most common constrained volumes, cylinder and cuboid, respectively. Both calculations agree well with Monte Carlo simulations. Additionally, the theoretical model of the residual gas damping presented in this work is in good agreement with the experimental results in the ground torsion pendulum test of LISA and its precursor LISA Pathfinder.
Impact of traditional physics lab instruction on students’ critical thinking skills in a Finnish context
Authors: Pirinen P , Lehtinen A , Holmes N G
Published: March 2023

Recent studies have given incentives to physics departments around the world to revise the learning goals of their lab courses to emphasize experimentation skills over reinforcing lecture content. Evaluation instruments have been developed to measure the achievement of learning goals, and one such instrument is the Physics Lab Inventory of Critical thinking (PLIC). The PLIC measures respondents’ ability to evaluate models, evaluate methods, and to suggest the next steps for an investigation. In the present work, we give consideration to the validity of our Finnish translation of the PLIC and we show results from our baseline study of first-year introductory lab courses with labs mixing content- and skills-related learning goals. We observed no statistically significant change in students’ critical thinking skills over the period of our study.
Monte Carlo study of cuprate superconductors in a four-band

d−p

model: role of orbital degrees of freedom
Authors: Watanabe Hiroshi , Shirakawa Tomonori , Seki Kazuhiro , Sakakibara Hirofumi , Kotani Takao , Ikeda Hiroaki , Yunoki Seiji
Published: March 2023

Understanding the various competing phases in cuprate superconductors is a long-standing challenging problem. Recent studies have shown that orbital degrees of freedom, both Cu e

g
orbitals and O p orbitals, are a key ingredient for a unified understanding of cuprate superconductors, including the material dependence. Here we investigate a four-band

d

−

p

model derived from the first-principles calculations with the variational Monte Carlo method, which allows us to elucidate competing phases on an equal footing. The obtained results can consistently explain the doping dependence of superconductivity, antiferromagnetic and stripe phases, phase separation in the underdoped region, and also novel magnetism in the heavily-overdoped region. The presence of p orbitals is critical to the charge-stripe features, which induce two types of stripe phases with s)-wave and d-wave bond stripe. On the other hand, the presence of

d

z
2

orbital is indispensable to material dependence of the superconducting transition temperature (

T

c

), and enhances local magnetic moment as a source of novel magnetism in the heavily-overdoped region as well. These findings beyond one-band description could provide a major step toward a full explanation of unconventional normal state and high

T

c

in cuprate supercondutors.
High power impulse magnetron sputtering of tungsten: a comparison of experimental and modelling results
Authors: Suresh Babu Swetha , Rudolph Martin , Ryan Peter John , Fischer Joel , Lundin Daniel , Bradley James W , Gudmundsson Jon Tomas
Published: March 2023

Here, we compare the ionization region model (IRM) against experimental measurements of particle densities and electron temperature in a high power impulse magnetron sputtering discharge with a tungsten target. The semi-empirical model provides volume-averaged temporal variations of the various species densities as well as the electron energy for a particular cathode target material, when given the measured discharge current and voltage waveforms. The model results are compared to the temporal evolution of the electron density and the electron temperature determined by Thomson scattering measurements and the temporal evolution of the relative neutral and ion densities determined by optical emission spectrometry. While the model underestimates the electron density and overestimates the electron temperature, the temporal trends of the species densities and the electron temperature are well captured by the IRM.
Discharge in air in contact with water: influence of electrical conductivity on the characteristics and the propagation dynamics of the discharge
Authors: Herrmann Antoine , Margot Joëlle , Hamdan Ahmad
Published: March 2023

Due to the high reactivity and the non-thermal properties of streamer discharges, they are applied in various fields, such as water treatment and medicine. Streamer discharges are usually produced in the gas phase before interacting with a liquid or solid surface. Although the dynamics of a streamer discharge in gases is well described, its propagation at liquid surfaces remains poorly understood. In this study, we investigate the influence of water electrical conductivity (σ), between 2 and 1000 µS cm−1, on the characteristics and propagation dynamics of pulsed positive DC nanosecond discharges with the solution serving as a cathode. σ strongly influences τ
r (the dielectric relaxation time), and two discharge modes may be obtained, depending on whether τ
r is shorter or longer than the delay to achieve breakdown (τ
pulse). This latter can be indirectly modified by adjusting the voltage amplitude (V
a). In the case of V
a = 14 kV, the breakdown voltage (V
bd) at low σ is lower than that measured at high σ, probably because τ
pulse < τ
r and > τ
r, respectively. In the case of V
a = 20 kV, V
bd decreases slightly with σ, probably because of the decrease of the resistivity of the global electrical circuit as τ
pulse ∼ τ
r for high σ. In addition to the electrical characterization, the dynamics of the discharge at the solution’s surface is investigated using 1 ns-time-resolved imaging. Its morphology was found to evolve from a disc to a ring before it splits into highly organized plasma dots (streamers’ head). The number (N
dots) and propagation velocity of plasma dots are determined as a function of σ. At V
a = 14 kV, N
dots does not vary significantly with σ despite the increase of V
bd; this latter likely compensates the neutralization of charge accumulated at the surface by ions in solution. In the case of V
a = 20 kV, N
dots decreases with σ, and it can be related to a decrease of accumulated charge at the water surface. Finally, based on the electrical measurements, we found that the charge per plasma dot (Q
dot) increases with σ, which does not correlate with the imaging results that show a short length of propagation at high σ. Then, considering the plasma dot mobility at low σ and the instantaneous propagation velocities at high σ, a more realistic Q
dot is measured.
Tunable Schottky barrier in a graphene/AlP van der Waals heterostructure
Authors: Zhang Zicheng , Shi Tianlong , He Jingjing , Liu Chunsheng , Meng Lan , Yan Xiaohong
Published: March 2023

The controllable modulation of the electronic properties of two-dimensional van der Waals (vdW) heterostructures is crucial for their applications in the future nanoelectronic and optoelectronic devices. In this paper, the electronic properties of a graphene/AlP heterostructure are theoretically studied by first-principles calculation. The results show that due to the weak vdW interaction between graphene and the AlP monolayer, both the Dirac semi-metallic properties of graphene and the semiconductivity properties of monolayer AlP are well retained. The graphene/AlP heterostructure forms a 0.41 eV p-type Schottky contact, and the barrier height and contact type can be successively controlled by the applied external electric field and vertical stress. When the applied electric field exceeds −0.5 V Å−1, the heterostructure interface changes from a p-type Schottky contact to an n-type Schottky contact. When the applied electric field exceeds 0.4 V Å−1 or the interlayer spacing is less than 3.1 Å, the interface contact type changes to Ohmic contact. These results indicate that the graphene/AlP heterostucture behaves as tunable Schottky barrier for potential applications in nano-devices.
New interaction solutions of the KdV-Sawada-Kotera-Ramani equation in various dimensions
Authors: Chen Wenxia , Tang Liangping , Tian Lixin
Published: March 2023

In this paper, the KdV-Sawada-Kotera-Ramani(KdVSKR) equation in various dimensions are studied. The bilinear form of the (1+1)-dimensional and (2+1)-dimensional KdVSKR equation are obtained by the independent transformation. Based on the Hirota bilinear method, we constructed new interaction solutions by studying the unknown nonlinear differential equations for the corresponding parameters. Three dimensional plots, density plots and contour plots provide us with a better understanding of visualizing the dynamic behavior of solutions.
Monopoles, strings and gravitational waves in non-minimal inflation
Authors: Maji Rinku , Shafi Qaisar
Published: March 2023

We discuss how in SO(10) grand unification an observable number density of topologically stable intermediate mass (∼ 1014 GeV) monopoles survive inflation driven by a Coleman-Weinberg potential and non-minimal coupling of the inflaton field to gravity. The scalar spectral index ns
is in excellent agreement with the current observations, and the tensor to scalar ratio r ≳ 0.003.
The model also predicts the presence of intermediate scale topologically stable cosmic strings, and their gravitational wave spectrum reflects the amount of cosmic inflation experienced by the associated symmetry breaking.
The discovery of these primordial monopoles and the stochastic gravitational wave background from the strings would provide important new insights regarding the symmetry breaking patterns in the early universe.
Bound on quantum fluctuations in gravitational waves from LIGO-Virgo
Authors: Hertzberg Mark P. , Litterer Jacob A.
Published: March 2023

We derive some of the central equations governing quantum fluctuations in gravitational waves, making use of general relativity as a sensible effective quantum theory at large distances. We begin with a review of classical gravitational waves in general relativity, including the energy in each mode. We then form the quantum ground state and coherent state, before then obtaining an explicit class of squeezed states. Since existing gravitational wave detections arise from merging black holes, and since the quantum nature of black holes remains puzzling, one can be open-minded to the possibility that the wave is in an interesting quantum mechanical state, such as a highly squeezed state. We compute the time and space two-point correlation functions for the quantized metric perturbations. We then constrain its amplitude with LIGO-Virgo observations. Using existing LIGO-Virgo data, we place a bound on the (exponential) squeezing parameter of the quantum gravitational wave state of ζ < 41.
Simulations of hot electron transport in radiation-ablated plasma
Authors: Zhao Bin , Tao Tao , Yan Rui , Zheng Jian
Published: March 2023

The transport of hot electrons in inertial confinement fusion (ICF) is integrated issue due to the coupling of hydrodynamic evolution and many physical processes. A hot electron transport code is developed and coupled with the radiation hydrodynamic code MULTI1D in this study. Using the code, the slowing-down process and ablation process of the hot electron beam are simulated. The ablation pressure scaling law of hot electron beam is confirmed in our simulations. The hot electron transport is simulated in the radiation-ablated plasmas relevant to indirect-drive ICF, where the spatial profile of hot electron energy deposition is presented around the shock compressed region. It is shown that the hot electron can prominently increase the total ablation pressure in the early phase of radiation-ablated plasma. So, our study suggests that a potential-driven symmetric mechanism may occur under the irradiation of asymmetric hot electron beam. The possible degradation from the hot electron transport and preheating is also discussed.
Symmetry-constrained quantum coupling in non-Fermi-liquid transport
Authors: Li Rong , She Zhen-Su
Published: March 2023

Finding the common origin of non-Fermi liquids (NFLs) transport in high-temperature superconductors (HTSCs) has proven to be fundamentally challenging due to the prominence of various collective fluctuations. Here, we propose a comprehensive non-Hermitian Hamiltonian (NHH) for quantum coupling of multiple scattering mechanisms associated with four types of order fluctuations. It predicts that the anticommutation symmetry of the spinor fermions constrains the scattering rate to a unified quadrature scaling, i.e.,

Γ
=

Γ
I

+

Γ
Q
2

+

(
μ

k
B

T
)

2

+

(
ν

μ
B

B
)

2

+

(

γ
E

E
)

2

. This scaling yields a comprehensive and accurate description of two widespread NFL behaviors in HTSCs, i.e., a temperature-scaling crossover between quadratic and linear laws and the quadrature magnetoresistance, validated by several dozens of data sets for broad phase regimes. It reveals that the common origin of these behaviors is the spinor-symmetry-constrained quantum coupling of spin-wave and topological excitations of mesoscopic orders. Finally, we show that this NHH can be easily extended to other complex quantum fluids by specifying the corresponding symmetries. It is concluded that this work uncovers a critical organization principle (i.e., the spinor symmetry) underlying the NFL transport, thus providing a novel theoretical framework to advance the transport theory of correlated electron systems.
Numerical simulation study of ionization characteristics of argon dielectric barrier discharge
Authors: Liu 刘 Guiming 桂铭 , Chen 陈 Lei 雷 , Zhao 赵 Zhibo 智博 , Song 宋 Peng 鹏
Published: March 2023

In order to better analyze the characteristics of particle distribution and its influencing factors in the ionized space during the process of coaxial dielectric barrier discharge, a self-designed two-dimensional axisymmetric structure exciter was used to carry out optical diagnosis, with the electron temperature calculated through Gaussian fitting. A plasma model was applied to conduct research on the discharge process through numerical simulation, with the changes in electron density and electron temperature were analyzed by using different discharge parameters. The research results show that with an increase in discharge voltage, pressure inside the reactor and relative permittivity, the discharge process is promoted. In addition, a rise in current density leads to an increase in the number of charged particles on the surface of the medium during the discharge process, while a rise in discharge intensity causes an increase in the electron density. Electron temperature decreases due to the increased loss of collision energy between particles. These results were confirmed by comparing experimental data with simulation results.
Turing/Turing-like patterns: Products of random aggregation of spatial components
Authors: Gao Jian , Wang Xin , Liu Xinshuang , Shen Chuansheng
Published: March 2023

Turing patterns are typical spatiotemporal ordered structures in various systems driven far from thermodynamic equilibrium. Turing’s reaction-diffusion theory, containing a long-range inhibiting agent and a local catalytic agent, has provided an explanation for the formation of some patterns in nature. Numerical, experimental and theoretical studies about Turing/Turing-like patterns have been generally focused on systems driven far from thermodynamic equilibrium. The local dynamics of these systems are commonly very complex, which brings great difficulties to understanding of formation of patterns. Here, we investigate a type of Turing-like patterns in a near-equilibrium thermodynamic system experimentally and theoretically, and put forward a new formation mechanism and a quantitative method for Turing/Turing-like patterns. Specifically, we observe a type of Turing-like patterns in starch solutions, and study the effect of concentration on the structure of patterns. The experimental results show that, with the increase of concentration, patterns change from spots to inverse spots, and labyrinthine stripe patterns appear in the region of intermediate concentration. We analyze and model the formation mechanism of these patterns observed in experiments, and the simulation results agree with the experimental results. Our conclusion indicates that the random aggregation of spatial components leads to formation of these patterns, and the proportion of spatial components determines the structures. Our findings shed light on the formation mechanism for Turing/Turing-like patterns.
An exact solution of the homogenous trimer Bose-Hubbard model
Authors: Pan Feng , Li Aoxue , Wu Yingxin , Draayer J P
Published: March 2023

It is shown that the homogenous three-site (trimer) Bose–Hubbard model with a periodic boundary condition can be solved exactly by using an extended Bethe ansatz based on the solution of the dimer model and the site-permutation symmetry. A solution of the model within the S
3 symmetric or non-symmetric subspace is presented. Coupled differential equations of a series of extended Heine–Stieltjes polynomials, the zeros of which are related to the solution of the model, are derived. Numerical examples of the solution of the model with

N
⩽
4

bosons, including the related Heine–Stieltjes polynomials and the Van Vleck polynomials, are presented, which serve to validate the procedure and illustrate the completeness of the solutions they render.