bluuebunny/crossref_metadata_2025_split huggingface dataset:
Macroscopic phenomenon of exchange coupling and microscopic effect on magnetization reversal in sintered Nd–Fe–B magnets
Authors: Wang Chao , Li Bang-chen , Fu Yuan-zhe , Bai Suo , Liu Yan-li , Li Zhu-bai 
Published: March 2024

Abstract
Permanent magnets of Nd13.5Fe79.18M1.52B5.8 and Nd13.5Fe79.76M0.94B5.8 were prepared, respectively, via strip casting, jet milling and sintering followed by annealing. By adding the non-ferromagnetic elements M (Al, Cu, Ga and Zr) into the magnets, it could not only modify the microstructure, but also regulate the exchange coupling effect in the sintered magnets. From the macroscopic point of view, the recoil loops exhibit spring behavior in Nd13.5Fe79.76M0.94B5.8, indicating that the energy barrier can be overcome by the intergranular exchange coupling. From the microcosmic point of view, the exchange coupling can increase the domain wall size by suppressing the nucleation of reversed domains, and so the activation volume increases with thermal activation. In Nd13.5Fe79.76M0.94B5.8 the exchange coupling effect is stronger, and both the coercivity of 15.0 kOe and the remanence of 14.3 kGs are a little higher than those of Nd13.5Fe79.18M1.52B5.8 magnets in which the content of non-ferromagnetic elements is a little higher and the exchange coupling effect is weaker. Thus, the exchange coupling does not decrease the coercivity due to the exchange coupling suppressing the nucleation of reversed domains, though the microstructure is inhomogeneous in the sintered magnets of Nd13.5Fe79.76M0.94B5.8. Reducing the defect size and decreasing the defect concentration should be a practical way to improve the coercivity in Nd–Fe–B permanent magnets.
Analysis of mechanisms of bubble characteristics and molten pool dynamics in EDM based on a three-phase flow model
Authors: Peng Weiye , Tang Jiajing , Li Zhengkai , Qiu Zhiwei , Yin Mulong 
Published: March 2024

Abstract
Bubble characteristics and bubble volume fraction have significant effects on crater morphology and machining efficiency during electrical discharge machining (EDM) in liquid. Therefore, there is a need to elucidate the mechanism of bubble characteristics in EDM and analyze the mechanism of crater formation based on these bubble characteristics. However, since EDM is a transient multiphysics process, it is extremely difficult to understand bubble characteristics using experimental methods. Therefore, the generation, expansion, explosion, and disappearance of bubbles during EDM were simulated based on a three-phase flow model in this study. The model used the phase field method to track the boundary motion, judged the existence mode of each phase according to the order parameter gradient function, and analyzed the formation of crater morphology by the gradient of surface tension in the molten pool. The motion process of bubbles, the material removal mode, and the formation mechanism of crater morphology during the pulsed discharge were analyzed using the model. The results revealed that the periodic motion of the plasma channel would drive the molten pool to produce the corresponding periodic motion, and the bubbles would grow following the periodic motion of the molten pool. The material was removed in different ways in different periods, among which the removal mode of molten splash was predominant. The surface tension gradient inside the molten pool, the periodic motion of the molten pool, and the hydrostatic pressure in the molten region had a combined effect on bubble motion, the flow of the molten pool, and the formation of the crater morphology.
Chiral spin textures creation and dynamics in a rectangular nanostructure
Authors: Kandukuri Sateesh , Garcia-Sanchez Felipe , Thiruvikraman P K , Satya Narayana Murthy V 
Published: March 2024

Abstract
Controlled creation of stable chiral spin textures is required to use them as an energy-efficient information carrier in spintronics. Here we have studied the stable creation of isolated chiral spin texture (skyrmion and antiskyrmion) and its pair through the magnetization reversal of a rectangular nanostructure using spin-polarized currents. An isolated spin texture is created through a negative current pulse. Dynamics of the stable spin texture are explored under external magnetic fields, and the resonant frequencies are calculated. A stable skyrmion pair is created using an asymmetric current pulse, and their interaction is studied using the Thiele equation. The stability of isolated or paired spin texture depends on the Dzyaloshinskii–Moriya interaction strength, spin-polarized current density, and pulse duration. In addition, the stability of the skyrmion pair depends on their initial separation, and a threshold for the separation between skyrmions of 78 nm is observed.
Source–drain switching characteristics when coupled with a gate-controlled DBD in a microplasma switch
Authors: Chen Lichi , Wang Yaogong , Li Xueying , Ma Xiaoqin , Wang Wenjiang , Zhang Xiaoning 
Published: March 2024

Abstract
Microplasma switches have attracted considerable attention in harsh environment applications, such as satellites, space exploration, nuclear reactors, and oil drilling, because of their inherent characteristics. A microplasma switch is generally constructed from a source, drain, and gate electrodes, and current conduction is generated between the drain and source (DS), and modulated by the gate. In this work, to improve the gate lifespan and device stability, a microplasma switch with a gate dielectric barrier structure is fabricated due to the even and stable discharge of a dielectric barrier discharge (DBD), and a parameterized nanosecond pulse voltage signal is applied to the gate. Under the effect of the DS voltage, a pulsed DS current is triggered by the gate pulse since a large number of charged particles are generated by the gate DBD, which shows that the DS switching behavior is triggered by the gate pulse. The microplasma switch operates stably (with an average delay jitter of less than 50 ps) at the repetition frequencies (up to 80 kHz). Moreover, the influence of experimental conditions on the switching performance is systematically investigated. The conduction current and delay, which are related to the discharge intensity and speed, are influenced by the electric-field strength of the channel (determined from the pulse amplitude and DS voltage) and its variation rate (determined from the rising and falling edge time of the pulse). In addition, the device performance is influenced by varying the breakdown voltage of the DS (determined from the gas pressure multiplied by DS spacing), which can result in variation of the working coefficient. It is also influenced by varying the wall voltage (decided by pulse width and frequency), which can result in the decrease in the total voltage of the channel.
Excitation-wavelength-dependent photoluminescence in GaAs nanowires under high-pressure
Authors: Yin Xuetong , Liang Yilan , Li Lixia , Liu Shuang , Pan Dong , Wang Peng 
Published: March 2024

Abstract
GaAs nanowires (NWs) have wide application potential as near-infrared optical devices and the high-pressure strategy has been applied to modulate their crystal and electronic structures. As another typical thermodynamic parameter, temperature can also affect the optical performance of semiconductors. Here we report the excitation-wavelength-dependent photoluminescence (EWDP) in GaAs NWs under high-pressure conditions. The pressure for achieving the maximum photoluminescence (PL) intensity and bandgap transition from direct to indirect of GaAs NWs varies (1.7–2.7 GPa) with the wavelength of the incident lasers (633–473 nm). The Raman peak of GaAs NWs shifts towards higher frequency with increasing excitation wavelengths at the same high-pressure conditions, revealing the stronger heating effect induced by incident laser with the shorter wavelength. The relative temperature difference in GaAs NWs induced by two different lasers can be estimated up to 537 K, and the strong heating effect suppresses the light-emission efficiency in GaAs NWs. With increasing the pressure, the relative temperature difference presents a gradual declining trend and PL intensity presents an opposite trend, which relates to the pressure-induced suppression of nonradiative recombination in GaAs NWs. Our study provides insights into the mechanisms for the EWDP effect and an alternative route to modulate the high-pressure performance of nanodevices.
The effects of nontoxic bio-based substances (egg white) on the performance and passivation of ZnO nanorods arrays-based light emitting devices
Authors: Chuang Sung-Hao , Feria Denice Navat , Lo Yan-Shawn , Hsieh Tung-Han , Lin Tai-Yuan 
Published: March 2024

Abstract
An innovative approach is proposed to passivate the existing defects from metal oxide semiconductors by functionalizing nontoxic bio-based substances. As a demonstration, we synthesized zinc oxide nanorods (ZnO NRs) using a hydrothermal method and incorporated chicken egg white (albumen) as a passivator to the defects. X-ray diffraction analysis of ZnO NRs shows enhanced quality and crystallinity features after incorporating albumen. XPS measurements were performed not only to introduce the chemical bonding between the albumen and the bare ZnO NRs but also specifically provide evidence of successful capping and defect passivation to the surface layer of ZnO NRs. It was observed that when the albumen was annealed, it formed sulfhydryl groups and disulfide bonds (which created disulfide bridges) from the chemical reaction in irreversible thermal denaturation. Steady-state photoluminescence of ZnO NRs showed two emission bands, i.e. near band-edge emission (NBE) and deep-level emission (DL). The NBE is significantly improved as compared to DL emission after capping and annealing the albumen, while the quenching of DL emission confirmed the reduced defects arising from the surface of ZnO NRs. The advantages and enhanced characteristics of the albumen-capped ZnO NRs led to fabricating a stable and highly efficient light-emitting device. This work opens the great potential of utilizing nontoxic and low-cost biomaterials in passivating the defects of metal oxide nanomaterials for the development of bio-inspired and stable optoelectronic devices.
Design of MFAC greenhouse temperature controller based on LESO with disturbance estimation and fuzzy controller with parameter tuning
Authors: Wang Lina , Li Xue , Xu Mengjie , Wang Binrui 
Published: March 2024

Abstract
The proper temperature is essential for the growth and development of greenhouse crops. Therefore, it is necessary to determine an appropriate greenhouse temperature automatic control strategy. In this paper, a model-free adaptive greenhouse temperature control strategy is proposed by combining a linear extended state observer and a fuzzy controller. Specifically, the linear extended state observer is introduced to estimate model approximation error generated by pseudo gradient estimation. The fuzzy controller is used to correct the system parameter

ρ

online. The simulation results show that when there is no disturbance, compared with the typical model-free adaptive scheme, the MAE and RMSE of the greenhouse temperature control scheme proposed in this paper are reduced by 57.55% and 5.40% respectively. In the presence of custom disturbances, the proposed control scheme still has a faster response speed, stronger robustness, and higher control accuracy. And the proposed method can reduce the frequent action of the actuator, thus effectively reducing the energy cost.
Active low frequency band expansion mechanism of electromagnetic wave absorber composite structure
Authors: Zhang Rui , Cao Xiaobo , Chen Xu , Yuan Xujin , Gao Yanze , Sun Yingjian , Chen Mingji 
Published: March 2024

Abstract
Bandwidth expansion of modern antennas and communication systems raises growing demand for electromagnetic wave absorber in compatibility equipment. Single absorption mechanism is hard to reach well-balanced characteristics including wide bandwidth, low frequency absorption and small thickness. Based on the composite structure concept, composite structure for electromagnetic wave absorber’s active low frequency band expansion is proposed, by combining circuit-analog absorber and active absorber to form a superimposed structure. The characteristic of composite structure is better than the single absorber structure, which improves enhancement mechanism brought by the composite structure. Sample fabrication and experiments indicate reflectivity curve envelope reaches −10 dB in 2.15–18 GHz frequency range (relative bandwidth 157.3%), and the tunable absorption frequency range in low-frequency domain is greater than 1.3 GHz. The structure has good adaptation on TE and TM polarizations, as well as good angle insensitivity. This composite structure has application potential in intelligent response system related with electromagnetic compatibility, energy absorption and object security management.
Sex differences in left atrial volumes, mechanics, and stiffness in primary mitral regurgitation—a combined 2D and 3D echocardiographic study
Authors: Berg-Hansen Christian E , Sindre Rasmus Bach , Grymyr Lisa M D , Rogge Barbara , Valeur Andreas E , Urheim Stig , Hung Judy , Cramariuc Dana 
Published: March 2024

Abstract

Aims
Mitral regurgitation (MR) causes left atrial (LA) enlargement and impaired reservoir function. We assessed whether changes in LA size, strain, and stiffness in significant (moderate or greater) primary MR are sex-specific.

Methods and results
In the 3D Echocardiography and Cardiovascular Prognosis in Mitral Regurgitation study, 111 patients with primary MR were prospectively investigated with 2D and 3D echocardiography. MR was severe if the 3D regurgitant fraction was ≥50%. LA size was assessed by maximum, minimum, and pre-A 3D volume (LAV), mechanics by peak reservoir (LASr) and contractile strain, and stiffness by the ratio: mitral peak E-wave divided by the annular e′ velocity (E/e′)/LASr. Women were older, had higher heart rate, and lower body mass index and MR regurgitant volumes (P &lt; 0.05). 3D LAV indexed for body surface area and LA contractile strain did not differ by sex, while LASr was lower (22.2 vs. 25.0%) and LA stiffness higher in women (0.56 vs. 0.44) (P &lt; 0.05). In linear regression analysis, female sex was associated with higher LA stiffness independent of age, minimum LAV, left ventricular global longitudinal strain, diabetes, and coronary artery disease (R2 = 0.56, all P &lt; 0.05). In logistic regression analysis, women had a four-fold (95% CI 1.2–13.1, P = 0.02) higher adjusted risk of increased LA stiffness than men.

Conclusion
Women with significant primary MR have more impaired LA reservoir mechanics and increased LA stiffness compared with men despite lower MR regurgitant volumes and similar indexed LA size. The findings reveal sex-specific features of LA remodeling in MR.

Trial Registration
ClinicalTrials.gov Identifier: NCT04442828
Life-threatening hemothorax due to rupture of pulmonary arteriovenous malformation during pregnancy
Authors: Kim Yeon Soo 
Published: March 2024

Abstract
Pulmonary arteriovenous malformation (PAVM) can worsen in pregnant women due to pregnancy-related physiological changes. If a PAVM ruptures, it can become life-threatening. A 24-year-old female patient at 22 weeks of gestation presented to the hospital with chest pain and dyspnea. A simple chest radiograph revealed that the right lung was almost completely collapsed due to massive pleural effusion, and the heart was displaced to the opposite side. Closed thoracostomy was performed and 2 l of blood was drained. Chest CT revealed the presence of a PAVM in the right upper lung. Emergency surgery was performed to resect the PAVM through thoracoscopic pulmonary wedge resection. The patient experienced disseminated intravascular coagulation and acute renal insufficiency after the surgery, but eventually recovered and was discharged without any complications on the sixth postoperative day.
Exploring Molecular Genetic Alterations and RAF Fusions in Melanoma: A Belvarafenib Expanded Access Program in Patients with RAS/RAF-Mutant Melanoma
Authors: Kim Kyoo Hyun , Cho Sungmin , Jeong Yeyeong , Baek Eun Sil , Lee Chung , Ryu Hyang-Joo , Noh Young Su , Hong Yoon-hee , Chung Kee Yang , Roh Mi Ryung , Oh Byung Ho , Kim Chang Gon , Jung Minkyu , Shin Sang Joon 
Published: March 2024

Abstract

Background
Melanoma incidence is on the rise in East Asia, yet studies of the molecular landscape are lacking in this population. We examined patients with melanoma who underwent next-generation sequencing (NGS) at a single tertiary center in South Korea, focusing on patients harboring NRAS or RAF alterations who received belvarafenib, a pan-RAF dimer inhibitor, through the Expanded Access Program (EAP).

Patients and Methods
Data were collected from 192 patients with melanoma who underwent NGS between November 2017 and May 2023. Variant call format data were obtained and annotated. Patients in the EAP received 450 mg twice daily doses of belvarafenib.

Results
Alterations in the RAS/RTK pathway were the most prevalent, with BRAF and NRAS alteration rates of 22.4% and 17.7%, respectively. NGS enabled additional detection of fusion mutations, including 6 BRAF and 1 RAF1 fusion. Sixteen patients with NRAS or RAF alterations received belvarafenib through the EAP, and disease control was observed in 50%, with 2 patients demonstrating remarkable responses.

Conclusions
Our study highlights the value of NGS in detecting BRAF, NRAS mutations and RAF fusions, expanding possibilities for targeted therapies in malignant melanoma. Belvarafenib showed clinical benefit in patients harboring these alterations. Ongoing trials will provide further insights into the safety and efficacy of belvarafenib.
Efficacy of traditional Chinese medicine containing hawthorn for hyperlipidemia: a systematic review and meta-analysis
Authors: Zhou Xiaoli , Chen Chun , Gao Zheng , Qian Zhiyong , Miao Jun 
Published: March 2024

Abstract
The traditional Chinese herb hawthorn is gaining attention for its potential to lower lipid levels due to its active components that positively influence lipid metabolism. Our meta-analysis of fourteen randomized controlled trials compared traditional Chinese medicine containing hawthorn with conventional lipid-lowering drugs for hyperlipidemia. Hawthorn-based medicine showed promise in reducing total cholesterol and triglycerides while increasing high-density lipoprotein cholesterol levels, albeit less effective than standard drugs in lowering low-density lipoprotein cholesterol. However, caution is needed due to methodological limitations in some trials, emphasizing the importance of further well-designed studies to clarify hawthorn’s efficacy in managing hyperlipidemia.
Rotational Malalignment After Intramedullary Nailing of Tibial Shaft Fractures Is Predictable
Authors: Cain Megan E. , Hendrickx Laurent A. M. , Sierevelt Inger , Kerkhoffs Gino M. M. J. , Jadav Bhavin , Doornberg Job N. , Jaarsma Ruurd L. 
Published: March 2024

OBJECTIVES:
Intramedullary nailing is the treatment of choice for most tibial shaft fractures (TSF). However, an iatrogenic pitfall may be rotational malalignment. The aim of this retrospective analysis was to determine predictors of rotational malalignment following intramedullary nailing of TSF.

METHODS:

Design:
Retrospective study.

Setting:
Single level 1 trauma center.

Patient Selection Criteria:
Patients who had a unilateral intramedullary nailing for TSF with a low-dose bilateral postoperative CT to assess rotational malalignment.

Outcome Measures and Comparisons:
Bivariable analysis followed by multivariable analysis was then undertaken to assess for any independent predictors, such as fracture type/sight, surgeon experience, and side of fracture, predictive of rotational malalignment.

RESULTS:
In total, 154 patients (71% male, median age 37 years) were included in this study. Thirty-nine percent of variability in postoperative rotational malalignment could be explained using a model including (increased) tibial torsion of the noninjured side (mean [38.9 degrees ± 9.02 degrees] considered normal tibial torsion), side of tibial fracture, and spiral-type tibial fracture (R2 = 0.39, P ≤ 0.001, F = 31.40). In this model, there was a negative linear association between degrees of torsion on the noninjured side and rotational malalignment (−0.45, P < 0.001)—as baseline torsion increased from mean by 1 degree, malrotation in the opposite direction of 0.54 degrees seen. Positive linear associations between right-sided TSF and rotational malalignment (8.59 P < 0.001) as well as spiral fractures and rotational malalignment (5.03, P < 0.01) were seen.

CONCLUSIONS:
This study demonstrates that baseline reduced (internal) tibial torsion of the noninjured limb, spiral fractures, and right-sided TSF are predictive of postoperative external rotational malalignment. Conversely, increased baseline (external) tibial torsion of the noninjured limb and left-sided TSF are predictive of postoperative internal rotational malalignment. Surgeons may use this regression model preoperatively to predict what sort of postoperative rotational difference their patient may be prone to.

LEVEL OF EVIDENCE:
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Responsiveness of the Zurich Claudication Questionnaire in Patients With Lumbar Spinal Stenosis Undergoing Nonsurgical Treatment
Authors: Minetama Masakazu , Kawakami Mamoru , Teraguchi Masatoshi , Nakagawa Masafumi , Yamamoto Yoshio , Sakon Nana , Nakatani Tomohiro , Matsuo Sachika , Nakagawa Yukihiro 
Published: March 2024

Study Design.
Secondary analysis of a randomized controlled trial.

Objective.
We investigated the ability to distinguish patients with lumbar spinal stenosis (LSS) who improved from those who did not after receiving nonsurgical treatment. We used the disorder-specific Zurich Claudication Questionnaire (ZCQ) satisfaction subscale as an external anchor and estimated the minimal clinically important differences (MCIDs) for the ZCQ symptom severity and physical function subscales.

Summary of Background Data.
The ZCQ satisfaction subscale effectively distinguishes surgical patients who improved from those who did not for LSS. However, its responsiveness in nonsurgical treatment has not been evaluated yet.

Methods.
Eighty-four patients with LSS who received supervised physical therapy or a home exercise program were included. Patients were classified as responders or nonresponders according to the cutoff of 2.5 for the ZCQ satisfaction subscales at six weeks and one year. The external responsiveness of the ZCQ satisfaction subscale was assessed using correlational and receiver-operating characteristic (ROC) curve analyses. MCIDs for the ZCQ symptom severity and physical function subscales were estimated using anchor and distribution approaches.

Results.
Pearson correlation coefficients between the changes in outcomes and the ZCQ satisfaction subscale at six weeks and one year were 0.37 to 0.58 (symptom severity) and 0.40 to 0.45 (physical function subscales) (>0.30 is considered a good anchor). The area under the ROC curve values were 0.66 to 0.72 and 0.63 to 0.71 for the symptom severity and physical function subscales, respectively (>0.7 is considered acceptable). The MCIDs at six weeks and one year estimated from anchor-based approaches were –0.64 to –0.13 (symptom severity) and –0.39 to 0.10 (physical function), and those from the distribution-based approaches were –0.31 to –0.30 and –0.29 to –0.27, respectively.

Conclusions.
The findings of this study suggest that the ZCQ satisfaction subscale has less ability to distinguish patients with LSS who improved in the ZCQ symptom severity and physical function subscales from those who did not after nonsurgical treatment, compared to those after surgical treatment.