bluuebunny/crossref_metadata_2025 huggingface dataset:
Economic Cost-Benefit Analysis of Nerve Implanted into Muscle versus Targeted Muscle Reinnervation versus Regenerative Peripheral Nerve Interface, for Treatment of the Painful Neuroma
Authors: Zamore Zachary , Yesantharao Pooja S. , Aravind Pathik , Dellon A. Lee
Published: February 2024

Background This study investigated the relative cost utility of three techniques for the management of symptomatic neuromas after neuroma excision: (1) implantation of nerve into muscle, (2) targeted muscle reinnervation (TMR), and (3) regenerative peripheral nerve interface (RPNI).

Methods The costs associated with each procedure were determined using Common Procedural Terminology codes in combination with data from the Centers for Medicaid and Medicare Services Physician and Facility 2020 Fee Schedules. The relative utility of the three procedures investigated was determined using changes in Patient-Reported Outcomes Measurement Information System (PROMIS) and Numeric Rating Scale (NRS) pain scores as reported per procedure. The relative utility of each procedure was reported in terms of quality-adjusted life years (QALYs), as is standard in the literature.

Results The least expensive option for the surgical treatment of painful neuromas was nerve implantation into an adjacent muscle. In contrast, for the treatment of four neuromas, as is common postamputation, TMR without a microscope was found to cost $50,061.55 per QALY gained, TMR with a microscope was found to cost $51,996.80 per QALY gained, and RPNI was found to cost $14,069.28 per QALY gained. While RPNI was more expensive than nerve implantation into muscle, it was still below the standard willingness-to-pay threshold of $50,000 per QALY, while TMR was not.

Conclusion Evaluation of costs and utilities associated with the various surgical options for the management of painful neuromas suggest that nerve implantation into muscle is the least expensive option with the best improvement in QALY, while demonstrating comparable outcomes to TMR and RPNI with regard to pain symptoms.
Postparetic Synkinesis: Objective and Subjective Comparisons of Depressor Anguli Oris Myectomies versus Depressor Anguli Oris and Buccinator Myectomies
Authors: Sanchez Cristina V. , Ercan Alp , Rozen Shai M.
Published: February 2024

Background Muscles affected by postparetic synkinesis have imbalanced tonicity that limit perioral mimetic movement and inhibit the ability to smile. The depressor anguli oris (DAO) muscle has been a common myectomy target for the treatment of perioral synkinesis. While addition of buccinator myectomies to DAO myectomies has risen, no studies have analyzed the effects of buccinator myectomies. The goal of this study was to evaluate and compare the effects of a DAO myectomy with and without concomitant buccinator myectomy through objective facial metrics and subjective patient-reported outcomes.

Methods This study is a retrospective review of patients with postparetic synkinesis who underwent DAO myectomy (DAO myectomy group) or DAO myectomy with buccinator myectomy (DAO + Buccinator myectomies group). Outcomes included postoperative differences in objective smile measures (smile angle, excursion, and dental show) using validated software and patient-reported outcomes using the Facial Disability Index (FDI) questionnaire and a myectomy-specific questionnaire.

Results After chart review, 18 patients were included in the DAO myectomy group and 19 in the DAO + Buccinator myectomies group. There were no significant postoperative differences between the groups in (1) smile excursion, angle, or dental show at resting, closed smile, or open smile (p > 0.05), (2) FDI physical and social scores, p = 0.198 and 0.932, respectively, or (3) myectomy-specific questionnaire responses (p > 0.05).

Conclusion The addition of a buccinator myectomy to a DAO myectomy does not provide significant clinical benefit when compared with an isolated DAO myectomy, based on objective measures and subjective patient-reported outcomes.
Giant Meningiomas Invading the Cavernous Sinus: The “Inevitable Ones”
Authors: Silva Carlos Eduardo da , Vidaletti Tamara
Published: February 2024

Introduction Giant meningiomas invading the cavernous sinus (GMICSs) are a subgroup of challenging tumors due to their volume and the extent of neurological impairment. Preserving quality of life is one of the most relevant aspects of treating patients with GMICS.

Methods A retrospective study was conducted for surgeries performed between 2012 and 2022, including 33 patients presenting meningiomas with the largest diameter of at least 5 cm invading the cavernous sinus. The data from surgical intervention, Simpson grade of resection, tumor location, and morbimortality related to the surgeries were reviewed.

Results The group comprised 25 women and 8 men with a median age of 56 years. The mean follow-up period was 52 months. The tumors were in the sphenoid wing, anterior clinoid, spheno-orbital, spheno-petroclival, petroclival, and Meckel's cave. Simpson grade I, II, and III were obtained in 70% of cases. The meningiomas were classified as WHO grade 1 in 94%, grade 2 in 3%, and grade 3 in 3%. The overall mortality was 3%. Permanent cranial nerve deficits occurred in 21%, transient cranial nerve deficits in 42%, cerebrospinal fistula in 15%, and hemiparesis in 18%. The recurrence/regrowth rate was 6%. The Karnofsky Performance Status score of 100 and 90 was 82%.

Conclusions The surgical treatment of GMICS is an effective treatment modality with acceptable morbimortality and good long-term control. Involvement of the internal carotid artery is essential to determine the extent of resection inside the cavernous sinus, and training in the microsurgical laboratory is mandatory for safe surgical treatment.
Brain-Derived Neurotrophic Factor is Associated with Self-Reported
Quality of Sleep in Type 2 Diabetes Patients in Ghana
Authors: Agyekum Jennifer Adjepong , Yeboah Kwame
Published: February 2024

Objective Sleep disturbances are common in patients with type 2 diabetes
(T2DM), and this exacerbates disease severity and results in poor quality of
life. Brain-derived neurotrophic factor (BDNF) has been reported to mediate the
association between T2DM and poor sleep health. The burden of self-reported poor
sleep quality and duration in T2DM and their association with serum BDNF levels
were investigated.

Methods In this case-control design, the Pittsburgh Sleep Quality
Instrument was used to assess self-reported sleep quality and duration in 100
patients with T2DM and 80 nondiabetic controls. Sociodemographic data and
medical history were collected from case notes and/or using a structured
questionnaire. Fasting venous blood samples (5 mL) were collected to measure
plasma lipid profile and serum BDNF levels.

Results patients with T2DM had low levels of BDNF, poor sleep quality
(61.9% vs 27.5%, p<0.001), and shorter sleep duration (6.1±2.2 vs 6.9±1.1 h,
p=0.003). T2DM status was associated with doubling the odds of poor sleep
quality [OR (95%CI)=2.06 (1.07–6.43), p=0.039] and 1.6 times the odds of short
sleep duration [1.63 (1.03–3.79), p=0.028]. Multivariable logistic regression
analysis revealed no association between serum BDNF levels and sleep status.
However, there was a negative biological interaction between T2DM and BDNF
levels on poor sleep quality, resulting in 0.28 relative excess risk due to the
interaction and a 12% attributable proportion due to the interaction.

Conclusion In this study population, patients with T2DM had a high burden
of self-reported poor quality of sleep and shorter sleep duration compared to
the nondiabetic controls. T2DM interacts negatively with serum BDNF levels to
affect sleep quality.
Effect of Colchicine Treatment on Clinical Course in Children with
PFAPA Syndrome
Authors: Bagrul İlknur , Aydin Elif Arslanoglu , Tuncez Serife , Baglan Esra , Özdel Semanur , Bülbül Mehmet
Published: February 2024

Introduction Periodic fever, aphthous stomatitis, pharyngitis, and
cervical adenitis syndrome (PFAPA) is the most common periodic fever condition
in children. There is no consensus on treatment to prevent attacks and reduce
their frequency. In this study, we aimed to evaluate the effectiveness of
colchicine treatment in PFAPA syndrome. In addition, we described the
demographic and clinical features of PFAPA patients.

Materials and Methods We retrospectively analyzed 58 PFAPA patients who
were started on colchicine treatment between January 2017 and January 2022.
Demographic data, clinical features, laboratory tests, genetic analysis of
MEditerranean FeVer (MEFV) mutations, and autoinflammatory disease activity
index (AIDAI) scores of all patients were evaluated. In addition, patients were
divided into two groups according to MEFV variants and compared.

Results Attack frequency, duration, and AIDAI scores decreased in all
patients after colchicine treatment. Duration of follow-up was 13.53±6.65
months. The median±IQR age at diagnosis was 3.2 (2–5) years. Thirty three
(56.9%) patients had heterozygous mutations of MEFV. The most common MEFV
variants were M694V (63.6%). There was no significant difference between the two
groups in terms of colchicine responses.

Conclusion Colchicine treatment is effective and safe in patients with
PFAPA who have frequent attacks. No association was established between the
presence of heterozygous mutations of MEFV and colchicine response.
Synthesis of Heterocycles by a C–C Cross-Coupling/Alkyne-Carbonyl-Metathesis Strategy
Authors: Langer Peter
Published: February 2024

The present article presents a personal account on the synthesis of heterocycles by the combination of regioselective Pd-catalyzed cross-coupling reactions of polyhalogenated heterocycles, i.e., Suzuki–Miyaura and Sonogashira reactions, with alkyne-carbonyl-metathesis (ACM) reactions. The products, which show interesting optical, electronic or medicinal properties, are not readily available by other methods.
Failure of Per-Oral Endoscopic Myotomy (POEM) for Achalasia Cardia—LES-Directed Therapy or Esophageal Body Therapy-Directed Therapy?: A Pictorial High-Resolution Esophageal Manometry (HREM) Case-Based Analysis
Authors: Sharma Zubin Dev , Puri Rajesh
Published: February 2024

Per-oral endoscopic myotomy (POEM) is one of the main modalities of treatment of achalasia cardia today across subtypes and we are increasingly seeing patients persistent or recurrent symptoms after POEM. An accurate high-resolution esophageal manometry (HREM) is one of the most important tests that can help us guide the treatment in cases of failure of POEM. HREM can help us direct the therapy. The therapy can be lower esophageal sphincter-directed therapy or esophageal body-directed therapy that can be ascertained using HREM. With this review, we detail the factors associated with failure of POEM, tests that can be utilized for its evaluation, and case-based analysis using HREM in patients of post-POEM failure.
Giant Cell Tumor of the Tendon Sheath of the Hand: Analysis of Factors Impacting Recurrence
Authors: Kolisetty Pavan Venkateswar , Ali Sheikh Sarfraz , Ahmad Imran , Sudhy Indrajith K. , Prakash Om , Kishore Y. Ranga
Published: February 2024

Background Giant cell tumors of the tendon sheath (GCTTS) of the hand are considered the second most common benign tumors of the hand after ganglion cysts. Excision biopsy is considered the standard treatment at present. They are notorious for having a very high rate of recurrence as given in many studies. Many factors are said to be associated with recurrence of the tumors. The goal of this study is to evaluate the long-term results of a series of 48 patients operated on at a single institute and to find out if there is any correlation between the proposed risk factors with recurrence.

Methods A retrospective analysis was done in cases of GCTTS operated on between 2015 and 2021. The patients were invited for follow-up for a minimum of 2 years, and the patient files were reviewed. Further data were collected at follow-up including recurrence, range of movement, sensation, skin necrosis, scarring, and digital neuropathy. A data analysis was done. The correlation between the proposed risk factors and recurrence was calculated with the Pearson correlation coefficient. A p-value of less than 0.05 was considered statistically significant.

Results During the 6 years, 48 patients were operated on. Recurrence was observed in eight patients (16%) at an average of 38.7 months from the time of surgery. Of the risk factors, tumors with satellite nodules and tumor adjacency to joint correlated significantly with recurrence. No complications were observed during follow-up.

Conclusion GCTTS of the hand has a high propensity to recur. The presence of satellite nodules and proximity to interphalangeal joints are two important risk factors for recurrence. Magnification during surgery ensures complete excision of the tumor and reduces the chance of recurrence.
Magnetic properties of the frustrated Ising chain
Authors: Laptiev D. V. , Kryvchikov O. O. , Savin Yu. V. , Slavin V. V.
Published: February 2024

Using the Kramers–Wannier transfer matrix method, we studied several decorated Ising chains. The exact expressions for thermodynamic characteristics, including the ground state characteristics, were obtained. We considered several modeling chains with different signs and absolute values of exchange constants for the nearest- and the next-nearest neighbors. For these models, we calculated the magnetization curves. The critical values of magnetic fields and corresponding magnetization plateau parameters were obtained. Analytic expressions for the ground state entropy were obtained for the chains with different interaction constants. The dependencies of the number of states with minimum energy (the degeneration of the ground state) as the function of the number of particles were found. It was shown that these dependencies are expressed in terms of well-known numerical sequences, namely Lucas numbers and Pell numbers, which, in the limit of a large number of particles, are proportional to the powers of the golden and silver sections. Therefore, the ground state entropy (per particle) of the systems under consideration can be described in terms of these sections and, therefore, is nonzero.
Short notes: Measurements on the heat capacity of thermal reduced graphene oxide down to 0.3 K
Authors: Sumarokov V. V. , Dolbin A. V. , Jeżowski A. , Szewczyk D. , Gnida D. , Vinnikov N. A. , Bagatskii M. I.
Published: February 2024

The specific heat of thermally reduced graphene oxide (trGO) was measured by a thermal relaxation method in the temperature range from 0.3 to 275 K. It was found that the temperature dependence of the heat capacity С(Т)/T vs T2 of trGO is nonmonotonic. It has been established that in the temperature range of 0.3–6 K there is an anomalous behavior of the temperature dependence of the heat capacity trGO, sharply changing its character. It is assumed that this anomaly is due to the influence of impurities and defects, structural features.
Optimizing parameter search for community detection in time-evolving networks of complex systems
Authors: Lima Dias Pinto Italo'Ivo , Garcia Javier Omar , Bansal Kanika
Published: February 2024

Network representations have been effectively employed to analyze complex systems across various areas and applications, leading to the development of network science as a core tool to study systems with multiple components and complex interactions. There is a growing interest in understanding the temporal dynamics of complex networks to decode the underlying dynamic processes through the temporal changes in network structures. Community detection algorithms, which are specialized clustering algorithms, have been instrumental in studying these temporal changes. They work by grouping nodes into communities based on the structure and intensity of network connections over time, aiming to maximize the modularity of the network partition. However, the performance of these algorithms is highly influenced by the selection of resolution parameters of the modularity function used, which dictate the scale of the represented network, in both size of communities and the temporal resolution of the dynamic structure. The selection of these parameters has often been subjective and reliant on the characteristics of the data used to create the network. Here, we introduce a method to objectively determine the values of the resolution parameters based on the elements of self-organization and scale-invariance. We propose two key approaches: (1) minimization of biases in spatial scale network characterization and (2) maximization of scale-freeness in temporal network reconfigurations. We demonstrate the effectiveness of these approaches using benchmark network structures as well as real-world datasets. To implement our method, we also provide an automated parameter selection software package that can be applied to a wide range of complex systems.
Bifurcation analysis of autonomous and nonautonomous modified Leslie–Gower models
Authors: Roy Subarna , Sk Nazmul , Kumar Tiwari Pankaj
Published: February 2024

In ecological systems, the predator-induced fear dampens the prey’s birth rate; yet, it fails to extinguish their population, as they endure and survive even under significant fear-induced costs. In this study, we unveil a modified Leslie–Gower predator–prey model by incorporating the fear of predators, cooperative hunting, and predator-taxis sensitivity. We embark upon an exploration of the positivity and boundedness of solutions, unearthing ecologically viable equilibrium points and their stability conditions governed by the model parameters. Delving deeper, we unravel the scenario of transcritical, saddle-node, Hopf, Bogdanov–Takens, and generalized-Hopf bifurcations within the system’s intricate dynamics. Additionally, we observe the bistable nature of the system under some parametric conditions. Further, the nonautonomous extension of our model introduces the intriguing interplay of seasonality in some crucial parameters. We establish a set of sufficient conditions that guarantee the permanence of the seasonally driven system. By conducting a numerical study on the seasonally forced model, we observe a myriad of phenomena manifesting the predator–prey dynamics. Notably, periodic solutions, higher periodic solutions, and bursting patterns emerge, alongside intriguing chaotic dynamics. Specifically, seasonal variations of the predator-taxis sensitivity and hunting cooperation can lead to the extinction of prey species and even the control of chaotic (higher periodic) solutions through the generation of a simple periodic solution. Remarkably, the seasonal forcing has the capacity to govern the chaotic behavior, leading to an exceptionally quasi-periodic arrangement in both prey and predator populations.
Excitation of cylindrical and spherical precursor solitons in a flowing dusty plasma: Experimental and simulation studies
Authors: Kumar Krishan , Bandyopadhyay P. , Singh Swarnima , Sen A.
Published: February 2024

We report the first laboratory observation of precursor cylindrical and spherical solitons excited in a flowing dusty plasma. The experiments are carried out in an inverted Π-shaped dusty plasma experimental device in which a dust cloud is created in a background Argon plasma using micrometer-sized Kaolin particles. Using the single gas injection technique, the dust fluid is made to flow in a controlled manner over a cylindrical (or a spherical) charged object for a range of flow velocities. When the flow velocity exceeds a critical value, cylindrical (or spherical) solitons are excited, which, in the frame of the dust fluid, travel in the upstream direction, while wake structures propagate in the downstream direction. Unlike one-dimensional solitons, the amplitudes of these higher dimensional solitons decrease with time (and hence distance) while maintaining constancy of the product of their amplitudes with the square of their widths. The spherical solitons decay at a rate faster than the cylindrical soliton. It is also found that their amplitudes and velocities increase, and their widths decrease with an increase in the dust fluid velocity. Furthermore, the radii of curvature of the cylindrical and spherical solitons decrease with an increase in the dust fluid flow velocity. A 3D molecular dynamics simulation of the excitation phenomenon provides a good theoretical support to the experimental observations.
Effect of Zn/Si ratio on conversion luminescent properties of Er3+/Yb3+ co-doped oxyfluoride glasses used for solar cells
Authors: Zhou Ziyou , Luo Zhiwei , Tong Juxia , Liang Haozhang , Lu Anxian
Published: February 2024

Er3+/Yb3+ co-doped Na2O–CaF2–ZnO–Al2O3–SiO2 glasses with different Zn/Si ratios were prepared using the melt-quenching technique. The thermal stability was investigated by differential scanning calorimetry. Additionally, the absorption spectra were also analyzed to gather more information about their properties. The down-conversion luminescence corresponding to the strongest fluorescence at a wavelength of 547 nm was obtained under the 378 nm excitation, and a 4S3/2 level fluorescence lifetime was studied. By utilizing a laser pump with a wavelength of 980 nm, the process of both up-conversion and down-conversion luminescence was accomplished. In particular, the glasses substantially enhance fluorescence properties when the Zn/Si ratio is about 0.16. The changes in the Zn/Si ratio lead to modifications in the glass network structure, changing the coordination field environment around the fluorescence center and ultimately impacting the luminescence properties of the rare-earth ions. These effects are evidenced through the findings obtained from Fourier transform infrared spectroscopy and fluorescence spectroscopy analysis of the glass material.
Hydrodynamic expansion and plume splitting of the ultrafast laser-induced plasma during ablation of multi-element metallic materials under atmospheric condition
Authors: Zhang Sijie , Shin Yung C.
Published: February 2024

In this study, the hydrodynamic expansion and splitting effect of ultrafast laser-induced plasma plume for multi-element alloys were studied. A fully coupled hydrodynamic model for femtosecond laser ablation of multi-element alloys was presented to study the ambipolar electric field during the plume expansion process. The model utilized a level-set equation to capture the interface between the condensed phase and the gaseous phase and accounted for the reaction between different species. A time-gate direct fluorescence measurement was conducted for the target material of brass, a Cu–Zn alloy, to validate the simulation results. The simulation results showed good agreement with the experimental results and were able to predict the plume-splitting effect. The ambipolar electric field induced by charged particle distribution difference was studied in detail. It was found that the ambipolar electric field was the dominant cause for the acceleration of ions, which yielded plume splitting during the expansion process. The fully coupled HD model was further used to explore the effect of the beam spot size, laser fluence, and the pulse width on plasma plume splitting.
How well do one-electron self-interaction-correction methods perform for systems with fractional electrons?
Authors: Zope Rajendra R. , Yamamoto Yoh , Baruah Tunna
Published: February 2024

Recently developed locally scaled self-interaction correction (LSIC) is a one-electron SIC method that, when used with a ratio of kinetic energy densities (zσ) as iso-orbital indicator, performs remarkably well for both thermochemical properties as well as for barrier heights overcoming the paradoxical behavior of the well-known Perdew–Zunger self-interaction correction (PZSIC) method. In this work, we examine how well the LSIC method performs for the delocalization error. Our results show that both LSIC and PZSIC methods correctly describe the dissociation of H2+ and He2+ but LSIC is overall more accurate than the PZSIC method. Likewise, in the case of the vertical ionization energy of an ensemble of isolated He atoms, the LSIC and PZSIC methods do not exhibit delocalization errors. For the fractional charges, both LSIC and PZSIC significantly reduce the deviation from linearity in the energy vs number of electrons curve, with PZSIC performing superior for C, Ne, and Ar atoms while for Kr they perform similarly. The LSIC performs well at the endpoints (integer occupations) while substantially reducing the deviation. The dissociation of LiF shows both LSIC and PZSIC dissociate into neutral Li and F but only LSIC exhibits charge transfer from Li+ to F− at the expected distance from the experimental data and accurate ab initio data. Overall, both the PZSIC and LSIC methods reduce the delocalization errors substantially.
Stress evolution in enamel coating/Ni-based alloy systems during isothermal oxidation
Authors: Yan Gaosheng , Wu Yihan , Liu Wenyuan , Yu Wenshan , Shen Shengping
Published: February 2024

This paper utilizes a coupled chemomechanical model that integrates chemical reactions, diffusion, and mechanical deformation to describe the high-temperature interfacial reactions and stress evolution within an enamel coating/Ni-based super-alloy system. Through finite element simulation, we conduct a comprehensive analysis of multiple reactions and processes at the interface. Experimental characterization of the concentration distribution of various elements is employed to verify the accuracy of the proposed chemomechanical model. Additionally, the simulation reveals that the interface region experiences compressive circumferential stress, which can potentially lead to interfacial failure due to buckling. On the other hand, the enamel coating undergoes tensile circumferential stress, resulting in the formation of vertical surface cracks. These findings hold practical implications for the development of advanced coatings with enhanced durability and performance. Future research can further optimize coating design and enhance the reliability of high-temperature applications based on these results.
Relaxation kinetics of interface states and bulk traps in atomic layer deposited ZrO2/β-Ga2O3 metal-oxide-semiconductor capacitors
Authors: Chen Jiaxiang , Qu Haolan , Sui Jin , Lu Xing , Zou Xinbo
Published: February 2024

The study of interface states and bulk traps and their connection to device instability is highly demanded to achieve reliable β-Ga2O3 metal-oxide-semiconductor (MOS) devices. However, a comprehensive analysis of the capture/emission behavior of interface states and bulk traps can be challenging due to widespread time constant distribution. In this study, using capacitance transient measurement tools, trap states of the ZrO2/β-Ga2O3 MOS gate stack were explicitly investigated, particularly its bias- and temperature-dependent relaxation kinetics. As forward bias is enlarged, it is observed that the interface state density (Dit) increases by 12.6%. Two bulk traps with discrete levels identified as 0.43 eV (E1) and 0.74 eV (E2) below the conduction band minimum were extracted by deep-level transient spectroscopy. It is further revealed that the emission processes of E1 and E2 are thermally enhanced, while the capture processes remain insensitive to temperature. The electric-field dependence of E1 indicates that the dominant mechanism follows the rule of Poole–Frenkel emission. The capacitance–voltage (C–V) hysteresis deteriorated at a higher forward bias due to the higher trap density and increased population of trapped charges. These findings provide an important framework for future device optimization to improve the reliability and performance of β-Ga2O3 MOS devices.
Mixing mechanism of power-law non-Newtonian fluids in resonant acoustic mixing
Authors: Huo Qiang , Wang Xiaopeng
Published: February 2024

Resonant acoustic mixing (RAM) is a widely applied technology that utilizes low-frequency vertical harmonic vibration for fluid transfer and mixing. However, the current research on the mixing mechanism of RAM technology primarily focuses on the initial mixing stages, neglecting the subsequent turbulent transition. This lack of understanding hinders the further improvement of RAM technology. This paper aims to investigate the mixing mechanism of power-law non-Newtonian fluids (NNF) in RAM using the phase field model and the spectral analysis. The study focuses on understanding the facilitating effect of turbulent transition in mixing and explores the influence of the power-law index and the excitation parameter on the mixing characteristics. The results indicate that the flow field experiences Faraday instability due to the intense perturbation during transient mixing. This leads to the fluid mixing through the development of large-scale vortex to small-scale vortex. During this process, the frequency components of the flow field are distributed around the working frequency, demonstrating transient and broad frequency characteristics. The steady state then dissipates energy through the viscous dissipation of small-scale vortices and ultimately relies on the single-frequency components such as submultiples and multiples excited by the nonlinear effect to complete the mixing. The mixing effects of NNF and Newtonian fluids (NF) are essentially the same, but they consume energy in different ways. The mixing uniformity and mixing efficiency of NNF increase with increasing vibration acceleration and decrease with increasing vibration frequency. These findings provide new insights into the RAM mechanism of power-law NNF.
Improved moth-flame algorithm based on cat chaotic and dynamic cosine factor
Authors: Xu Chenhua , Zhang Wenjie , Tu Zhicheng , Liu Dan , Cen Jian , Song Haiying
Published: February 2024

The moth-flame algorithm shows some shortcomings in solving the complex problem of optimization, such as insufficient population diversity and unbalanced search ability. In this paper, an IMFO (Improved Moth-Flame Optimization) algorithm is proposed to be applied in solving the optimization problem of function. First, cat chaotic mapping is used to generate the initial position of moth to improve the population diversity. Second, cosine inertia weight is introduced to balance the global and local search abilities of the algorithm. Third, the memory information in the particle swarm algorithm is introduced into the iterative process of the algorithm to speed up the convergence of the population. Finally, Gaussian mutation strategy is used in the current optimal solution to avoid the algorithm from falling into the local optimum. Simulation experiments are conducted on 11 benchmark test functions, compared with other improved MFO (Moth-Flame Optimization) algorithms and classical optimization algorithms. The results show that the IMFO has higher accuracy and stability in solving the above-mentioned test functions. The proposed algorithm is experimented and verified by optimizing the KELM (Kernel Extreme Learning Machine) in an engineering example and exhibits a better optimization performance.
Promoting Na-ion storage in P2-Na0.67Ni0.33Mn0.67O2 cathode via synergetic Ti and Zn Co-incorporation
Authors: Chen Di , Zhang Haolin , Yang Hui Ying , Yu Caiyan , Bai Ying
Published: February 2024

P2-Na0.67Ni0.33Mn0.67O2 (NNMO) is regarded as a promising cathode candidate for sodium-ion batteries due to its high energy density. However, the electrochemical performance is hindered by Na+/vacancy order, irreversible P2–O2 phase transition at high voltage (>4.2 V), and harmful oxygen evolution. Herein, a synergetic Zn and Ti co-incorporation tactic is proposed for designing a Na0.67Ni0.29Zn0.04Mn0.63Ti0.04O2 (NNZMTO) cathode to overcome the above-mentioned challenges. First, the incorporated Ti heteroatom could break down Na+/vacancy order of NNMO by taking advantage of a similar ionic radius and substantially different Fermi levels with host Mn atom. Subsequently, the introduced Zn heteroatom could induce local Na–O–Zn configurations, buffer interlayer O2−–O2− electrostatic repulsion, as well as inhibit unfavorable phase transition. Moreover, the d10 band of Zn is lower than the oxygen states, and the Zn behaves like an s/p metal with oxygen, thus avoiding O2 release. Notably, in comparison with highly oxidized (Ni4+/Mn4+O6)δ− octahedron, the partial Na+ for charge neutrality in alkali metal layers could be well maintained in the as-designed (Zn2+/Ti4+O6)δ′−, which could be served as “pillars” to avoid layer gliding and structural collapse in the c-direction. As a result, an excellent electrochemical performance with high specific capacity of 90.9 mA h g−1 at 7 C could be retained for NNZMTO thanks to the synergetic effect from Ti and Zn incorporation. This study provides deep insights for designing superior layered cathode via conducting a rational cations co-incorporation strategy.
Exploration of the mechanical properties of carbon-incorporated amorphous silica using a universal neural network potential
Authors: Sakakima Hiroki , Ogawa Keigo , Miyazaki Sakurako , Izumi Satoshi
Published: February 2024

C-incorporated amorphous silica (a-SiOC) is expected to be a significant dielectric film for miniaturized semiconductor devices. However, information on the relationship among its composition, atomic structures, and material properties remains insufficient. This study investigated the dependence of the elastic modulus on the C content in a-SiOC, employing a universal neural network interatomic potential to realize a high-accuracy and high-speed simulation of multicomponent systems. The relationship between elastic modulus and atomic network structures was explored by fabricating 480 amorphous structures through the melt-quenching method without predetermined structure assumptions. The bulk modulus increased from 45 to 60 GPa by incorporating 10% C atoms under O-poor conditions and 20% C atoms under O-rich conditions, respectively. This result is attributed to the formation of denser crosslinking atomic network structures. In particular, the C atoms bonded with the Si atoms with higher coordination under O-poor conditions, whereas they tend to bond with O atoms under O-rich conditions, breaking the SiO2 network. Large C clusters precipitated as the C fraction was increased under O-rich conditions. Gas molecules, such as CO and CO2, were also generated. These results are consistent with reported ab initio calculation results of the formation energies of C defects and gas molecules in SiO2. The findings suggest that realizing O-poor conditions during deposition is crucial for fabricating stronger dielectric films. Therefore, this work contributes to understanding the fabrication of stronger dielectric films and elucidating the underlying mechanism of C cluster formation.
Broadband acoustic bend composed of homogeneous curved waveguides in quasi-two-dimensional space
Authors: Liu Chao , Zhou Jiaojiao , Zhou Yangyang , Xu Lin , Chen Huanyang
Published: February 2024

By exploring equivalent acoustic path length between inhomogeneous medium and homogenous curved geometry, we present a broadband acoustic bend composed of homogeneous curved waveguides in quasi-two-dimensional space. Simultaneous control of the wavefront and phase accumulation of acoustic waves is achieved by designing the embedding geometry of homogeneous curved waveguides with subwavelength ports, guaranteeing both the bending effect and extremely high transmission. Unlike metamaterials-based wave bends, homogeneous curved waveguides, filled with background air, exhibit promising broadband properties. Moreover, we propose a broadband acoustic splitter by mirroring the acoustic bend. Simulation results demonstrate functionalities of our designs.
Machine-learned atomic cluster expansion potentials for fast and quantum-accurate thermal simulations of wurtzite AlN
Authors: Yang Guang , Liu Yuan-Bin , Yang Lei , Cao Bing-Yang
Published: February 2024

Thermal transport in wurtzite aluminum nitride (w-AlN) significantly affects the performance and reliability of corresponding electronic devices, particularly when lattice strains inevitably impact the thermal properties of w-AlN in practical applications. To accurately model the thermal properties of w-AlN with high efficiency, we develop a machine learning interatomic potential based on the atomic cluster expansion (ACE) framework. The predictive power of the ACE potential against density functional theory (DFT) is demonstrated across a broad range of properties of w-AlN, including ground-state lattice parameters, specific heat capacity, coefficients of thermal expansion, bulk modulus, and harmonic phonon dispersions. Validation of lattice thermal conductivity is further carried out by comparing the ACE-predicted values to the DFT calculations and experiments, exhibiting the overall capability of our ACE potential in sufficiently describing anharmonic phonon interactions. As a practical application, we perform a lattice dynamics analysis using the potential to unravel the effects of biaxial strains on thermal conductivity and phonon properties of w-AlN, which is identified as a significant tuning factor for near-junction thermal design of w-AlN-based electronics.
Solute band transport in electroosmotic-pressure-driven flow of Carreau–Yasuda fluid over micropillar arrays
Authors: Mahapatra Bimalendu , Jana Rupayan , Bandopadhyay Aditya
Published: February 2024

In this study, we numerically investigate the transport and dispersion characteristics of a neutral solute band in a fluid following generalized Carreau–Yasuda constitutive equations. The combined action of electroosmotic forcing and pressure gradient drives the flow through a microchannel embedded with micropillars. We analyze the band transport process by altering the flow-controlling parameters and fluid rheology. We observe an enhancement in band dispersion with increasing solute diffusivity. An augmentation in band dispersion is achieved using bluff micropillar designs compared to the streamlined micropillars. We also observe that the dispersion of solute band is less in shear-thickening fluids than in shear-thinning fluids. In a mixed electroosmotic-pressure-driven flow, the favorable pressure gradient conditions enhance the band dispersion phenomenon. Our results may prove valuable in understanding solute transport dynamics in non-Newtonian fluids, which has implications for lab-on-a-chip diagnostics and precise drug delivery.
Simulating multiphase flow in fractured media with graph neural networks
Authors: Jiang Jiamin
Published: February 2024

Numerical modeling of flow dynamics with multiple fluid phases in subsurface fractured porous media is of great significance to numerous geoscience applications. Discrete fracture-matrix (DFM) approaches become popular for simulating fractured reservoirs in the last decade. Data-driven surrogate models can provide computationally efficient alternatives to high-fidelity numerical simulators. Although convolutional neural networks (CNNs) are effective at approximating the space-time solutions of multiphase flowing processes, it remains difficult for CNNs to operate upon DFMs with unstructured meshes. To tackle this challenge, we leverage graph neural networks (GNNs) for surrogate modeling of an embedded DFM model. The results of two-dimensional cases with complex fracture systems show that the learned surrogates precisely capture the effect of the variations in fracture connectivity and forecast dynamic pressure and saturation solutions with high accuracy. Furthermore, our GNN-based models exhibit promising generalizability to fracture networks with different geometries and numbers of fractures that are not encountered from the training dataset.
Separation-induced transition on a T106A blade under low and elevated free stream turbulence
Authors: Sengupta Aditi , Gupta Nivedita , Ubald Bryn Noel
Published: February 2024

The separation-induced transition on the suction surface of a T106A low pressure turbine blade is a complex phenomenon with implications for aerodynamic performance. In this numerical investigation, we explore an adverse pressure gradient-dominated flow subjected to varying levels of free stream excitation, as the underlying separation-induced transition is a critical factor in assessing blade profile loss. By comprehensively analyzing the effects of free stream turbulence (FST) on the transition process, we delve into the various mechanisms which govern the instabilities underlying bypass transition by studying the instantaneous enstrophy field. This involves solving the two-dimensional (2D) compressible Navier–Stokes equation through a series of numerical simulations, comparing a baseline flow to cases where FST with varying turbulent intensity (Tu=4% and 7%) is imposed at the inflow. Consistent with previous studies, the introduction of FST is observed to delay flow separation and trigger early transition. We explore the different stages of bypass transition, from the initial growth of disturbances (described by linear stability theory) to the emergence of unsteady separation bubbles that merge into turbulent spots (due to nonlinear interactions), by examining the vorticity dynamics. Utilizing the compressible enstrophy transport equation for the flow in a T106A blade passage, we highlight the various routes of bypass transition resulting from different levels of FST, emphasizing the relative contributions from baroclinicity, compressibility, and viscous terms.
Investigation of atomic layer deposition methods of Al2O3 on n-GaN
Authors: Tadmor Liad , Vandenbroucke Sofie S. T. , Bahat Treidel Eldad , Brusaterra Enrico , Plate Paul , Volkmer Nicole , Brunner Frank , Detavernier Christophe , Würfl Joachim , Hilt Oliver
Published: February 2024

In this work, three atomic layer deposition (ALD) approaches are used to deposit an Al2O3 gate insulator on n-GaN for application in vertical GaN power switches: thermal ALD (ThALD), plasma-enhanced ALD (PEALD), and their stacked combination. The latter is a novel method to yield the most ideal insulating layer. Also, the influence of an in situ NH3 or H2 plasma pre-treatment is studied. Planar MIS capacitors are used to investigate the electrical properties and robustness of the gate insulators. In vacuo x-ray photoelectron spectroscopy (XPS) is used to study the changes in chemical composition after every surface treatment. XPS shows that all plasma pre-treatments efficiently remove all carbon contamination from the surface, but only NH3 plasma is observed to additionally remove the native oxide from the n-GaN surface. The water precursor step in the ThALD process does not completely remove the CH3 ligands of the trimethylaluminum precursor step, which might electrically be associated with a reduced forward bias robustness. The O2 plasma step in the PEALD process is associated with the removal of carbon and a tremendous increase of the O content in the GaN surface region. Electrically, this strongly correlates to an enhanced forward bias robustness and an increased forward bias hysteresis, respectively. The ThALD/PEALD stack method mitigates the shortcomings of both ALD processes while maintaining its advantages. Electrical measurements indicate that the stack method alongside NH3 plasma pretreatment provides the best characteristics in terms of hysteresis, threshold voltage, forward bias robustness, and interface trap density of states.
Nonreciprocal microwave-optical entanglement in a magnon-based hybrid system
Authors: Zheng Qianjun , Zhong Wenxue , Cheng Guangling , Chen Aixi
Published: February 2024

We propose a theoretical scheme for the generation of nonreciprocal microwave-optical entanglement in a magnon-based hybrid system where an optical photon in a spinning resonator is coupled to a phonon representing the quantum of the mechanical deformation of a yttrium iron garnet crystal via radiation pressure. Meanwhile, the magnon interacts with the phonon and the microwave through the magnetostrictive and magnetic dipole–dipole interactions, respectively. By spinning the resonator, the light driven in opposite directions propagates irreversibly, which leads to the classical nonreciprocity of mean optical photon numbers. Strikingly, the nonreciprocal entanglement between microwave and optical photons can be generated owing to the Fizeau light-dragging effect. Physically, the magnon–phonon entanglement induced by the magnomechanical parametric downconversion interaction is partially transferred to the microwave-optical subsystem through magnon-microwave and optomechanical state-exchange interactions. Moreover, the nonreciprocity of entanglement can be manipulated by properly choosing various system parameters and the ideal nonreciprocal microwave–optical entanglement could be achieved, in which the entanglement depending on the effective optical detuning is present in a chosen direction but disappears in the other direction. Our work could be applied in the multi-task quantum information processing and construction of chiral quantum networks.
Designing 3D multicomponent self-assembling systems with signal-passing building blocks
Authors: Evans Joshua , Šulc Petr
Published: February 2024

We introduce an allostery-mimetic building block model for the self-assembly of 3D structures. We represent the building blocks as patchy particles, where each binding site (patch) can be irreversibly activated or deactivated by binding of the particle’s other controlling patches to another particle. We show that these allostery-mimetic systems can be designed to increase yields of target structures by disallowing misassembled states and can further decrease the smallest number of distinct species needed to assemble a target structure. Next, we show applications to design a programmable nanoparticle swarm for multifarious assembly: a system of particles that stores multiple possible target structures and a particular structure is recalled by presenting an external trigger signal. Finally, we outline a possible pathway for realization of such structures at nanoscale using DNA nanotechnology devices.
Spin-torque nano-oscillator based on two in-plane magnetized synthetic ferrimagnets
Authors: Monteblanco E. , Garcia-Sanchez F. , Romera M. , Gusakova D. , Buda-Prejbeanu L. D. , Ebels U.
Published: February 2024

We report the dynamic characterization of the spin-torque-driven in-plane precession modes of a spin-torque nano-oscillator based on two different synthetic ferrimagnets: a pinned one characterized by a strong Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction, which is exchange-coupled to an antiferromagnetic layer; and a non-pinned one characterized by weak RKKY coupling. The microwave properties associated with the steady-state precession of both synthetic ferrimagnets (SyFs) are characterized by high spectral purity and power spectral density. However, frequency dispersion diagrams of the damped and spin-transfer torque modes reveal drastically different dynamical behavior and microwave emission properties in both SyFs. In particular, the weak coupling between the magnetic layers of the non-pinned SyF raises discontinuous dispersion diagrams suggesting a strong influence of mode crossing. An interpretation of the different dynamical features observed in the damped and spin-torque modes of both SyF systems was obtained by solving simultaneously, in a macrospin approach, a linearized version of the Landau–Lifshitz–Gilbert equation including the spin-transfer torque term.