Ultrasonics Sonochemistry最新文献

{"title":"Theoretical and experimental research on the impacts of the Joukowsky hydrofoils on the bubble collapse dynamics within a confined space","authors":"Junwei Shen ,&nbsp;Hongbo Wang ,&nbsp;Cheng Zhang ,&nbsp;Yuning Zhang ,&nbsp;Yuning Zhang","doi":"10.1016/j.ultsonch.2024.107174","DOIUrl":"10.1016/j.ultsonch.2024.107174","url":null,"abstract":"<div><div>The present paper investigates the bubble collapse dynamics near hydrofoils within a confined space. Experiments involving high-speed photography reveal in detail the typical bubble morphological evolution near different hydrofoils between two glass plates (namely the confined space), and the partitioning of the thickness-related and camber-related parameters is analyzed quantitatively. Based on conformal transformation, the liquid velocity field and Kelvin impulse are used to analyze the bubble collapse characteristics qualitatively and quantitatively, including the bubble interface motion, cross-sectional roundness, and collapse jet. The main conclusions are summarized as follows. (1) The bubble morphological evolution near the hydrofoils can be categorized into five typical collapse shapes, and their partition ranges are significantly affected by the thickness-related and camber-related parameters. (2) The thickness-related hydrofoil parameter positively correlated with the bubble interface motion and cross-sectional roundness, while the camber-related parameter is inversely correlated with them. (3) High-velocity regions between the bubble and the hydrofoil head and tail endpoints explain the bubble interface depressions observed in the experiments</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107174"},"PeriodicalIF":8.7,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrasonication modifies the structural, thermal and functional properties of pumpkin seed protein isolate (PSPI)","authors":"Mehvish Habib ,&nbsp;Sakshi Singh ,&nbsp;Sameer Ahmad ,&nbsp;Shumaila Jan ,&nbsp;Ankit Gupta ,&nbsp;Kulsum Jan ,&nbsp;Khalid Bashir","doi":"10.1016/j.ultsonch.2024.107172","DOIUrl":"10.1016/j.ultsonch.2024.107172","url":null,"abstract":"<div><div>Protein isolates from pumpkin seeds were prepared and then treated with high-intensity ultrasound (HIUS) using a probe-based method. The impact of ultrasonication on the physicochemical, molecular, and thermal properties of these isolates were analyzed and compared to untreated controls. Results showed significant improvements (p ≤ 0.05) in color (L*, a*, b* values), solubility, emulsification capacity, and stability, as well as a reduction in molecular weight, indicating enhanced functionality of the pumpkin seed protein isolates (PSPIs) after HIUS treatment. However, HIUS treatment decreased the denaturation temperature (Td), denaturation enthalpy (ΔH), thermal stability, and particle size of the isolates. With treatment durations ranging from 5 to 20 min, T_d dropped from 67.31 °C to 56.38 °C, and ΔH declined from 45.78 to 35.43 J/g, likely due to structural and conformational modifications from ultrasonic-induced molecular bond disruptions. The greatest reduction in particle size, from 117.46 μm to 85.26 μm, was observed after 20 min of ultrasonication. X-ray diffraction (XRD) analysis showed two distinct diffraction peaks at 2θ = 10° and 2θ = 20°, indicating altered crystallite sizes post-ultrasound treatment. Ultrasonication induced structural and conformational changes in the pumpkin seed protein isolates, as confirmed by SDS-PAGE and weight loss analyses. Alterations in the SDS-PAGE profile and reduced weight loss were associated with improved solubility and enhanced thermal and functional properties in the treated pumpkin seed protein isolates. This emphasizes the potential of PSPI to increase their value-added potential through ultrasonication.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107172"},"PeriodicalIF":8.7,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogel carrier with bubble vibration enhancer for ultrasound-triggered drug release","authors":"Ryuto Yamakawa ,&nbsp;Hiroaki Onoe ,&nbsp;Yuta Kurashina","doi":"10.1016/j.ultsonch.2024.107173","DOIUrl":"10.1016/j.ultsonch.2024.107173","url":null,"abstract":"<div><div>Hydrogel-based drug carriers provide on-demand drug release via external stimuli. Ultrasound is a promising method because of the potential for remotely releasing the drug. However, intense ultrasound irradiation has been required in previous studies. This paper reports drug model release from hydrogel carriers encapsulating bubble vibration enhancers (BVEs) consisting of microbubbles coated with a lipid membrane. Vibration of BVEs induced by ultrasound stimulation promoted the release of drug models with ultrasound irradiation controlled to a biologically safe acoustic pressure based on spatial-peak temporal-average intensity (<em>I_SPTA</em>). The release ratio increased significantly from 2.3 % without BVEs and ultrasound to 10.2 % with both. To evaluate the frequency response, the release ratio was measured at three different ultrasound frequencies (0.3, 1.8, and 2.5 MHz), showing increased efficiency as the frequency approached the resonance frequency of the BVEs. For <em>in vivo</em> applications, hydrogel microspherical carriers with BVEs achieved a 12 % release ratio. Poly-L-lysine coating successfully suppressed the drug release to 0.2 %. The carriers demonstrated repeated responsiveness when ultrasound was applied in three 5-minute intervals. The hydrogel carrier encapsulating BVEs we proposed is a promising <em>in vivo</em> device capable of releasing drugs on demand by ultrasound irradiation based on its high biosafety and acoustic responsiveness.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107173"},"PeriodicalIF":8.7,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of driving frequency and power on droplet size atomized by a multimodal transducer","authors":"Weiquan Wang ,&nbsp;Zhirui Chen ,&nbsp;Hiroshi Hasegawa ,&nbsp;Kohsuke Hirano ,&nbsp;Chikahiro Imashiro ,&nbsp;Takeshi Morita","doi":"10.1016/j.ultsonch.2024.107166","DOIUrl":"10.1016/j.ultsonch.2024.107166","url":null,"abstract":"<div><div>Ultrasonic atomization is used in various applications such as medical devices, material synthesis, and humidity control. To meet the needs of different applications, the required droplet size ranges from a few microns to several hundred microns. In this study, we realized wideband multiple-frequency atomization with a multimodal transducer, which could control the size of atomized droplets by switching operating frequencies. A parabolic reflector served to focus the incident ultrasound waves, and a circular plate was employed to excite bending modes. By comparing the results of frequency response experiments with those of finite element simulation, nine different bending modes were acquired in the range of 500–2500 kHz. Then, 734, 949, 1530, and 2063 kHz were selected to examine atomization performance for producing 1–10 μm water droplets. The relationship between the droplet diameter and the operating frequency was clarified. The droplet diameter was found to follow a log-normal distribution. At these four frequencies, the mean droplet diameter was 7.71, 6.57, 4.87, and 4.43 μm, respectively, meaning that the diameter decreased with increasing frequency. The mean droplet diameter decreased with increasing input power at 734 kHz, whereas at 2063 kHz, no significant trend was shown. Furthermore, the atomization rate was found to increase at higher power and exhibited a frequency dependence. These results indicated that the multimodal transducer has promising potential for high-frequency ultrasonic atomization and the capacity to control the droplet size.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107166"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of ultrasound on the functional properties and structural changes of chicken liver insoluble proteins isolated by isoelectric solubilization/precipitation","authors":"Rongrong Mao ,&nbsp;Guoyuan Xiong ,&nbsp;Haibo Zheng ,&nbsp;Jun Qi ,&nbsp;Chunhui Zhang","doi":"10.1016/j.ultsonch.2024.107165","DOIUrl":"10.1016/j.ultsonch.2024.107165","url":null,"abstract":"<div><div>The studies investigated the effects of different ultrasonic powers (180, 360 and 540 W) on the functional properties and structural changes of chicken liver insoluble proteins (CLIPs) isolated by isoelectric solubilization/precipitation (ISP) (with alkaline solubilization at pH 11.0 and pH 12.0 respectively, and acid precipitation at pH 5.5). Results indicated that ultrasonic significantly increased the solubility of ISP-isolated CLIPs, and narrowed the particle size distribution of D₃,₂ and D₄,₃ (<em>P</em> &lt; 0.05). The highest solubility was observed at pH 11.0 and 360 W ultrasound treatment, reaching 77.26 %. The ultrasonic with 360 W exhibited higher shear stress and apparent viscosity. Spectroscopy revealed that compared to without ultrasonic treatment, there was an increase in β-sheet and random curling content accompanied by a decrease in β-turn and α-helix structure when ultrasonication. Ultrasound altered the tyrosine hydrophobic residues to be exposed to the surface of the ISP-isolated CLIPs, thus improving the hydrophilicity. Overall, ultrasound combined with ISP treatment effectively improved the functional properties of CLIPs, and it might be a potential, safe and efficient method for improving the processing properties and broadening the application of insoluble animal-derived proteins.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107165"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142722707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancements in Acoustic Cavitation Modelling: Progress, Challenges, and Future Directions in Sonochemical Reactor Design","authors":"T.Joyce Tiong ,&nbsp;Jin Kiat Chu ,&nbsp;Khang Wei Tan","doi":"10.1016/j.ultsonch.2024.107163","DOIUrl":"10.1016/j.ultsonch.2024.107163","url":null,"abstract":"<div><div>This review provides a comprehensive overview of ultrasonic wave propagation, with a primary focus on high-power ultrasound systems where cavitation bubbles are likely to occur. The review is structured to guide readers through the historical development of cavitation models, from early works such as the Rayleigh-Plesset equation to more advanced numerical approaches. It explores the dynamics of cavitation bubbles, their physical effects, and the key factors influencing bubble formation, growth, and collapse. In addition to bubble-induced cavitation, the review addresses nonlinear wave propagation in the absence of bubbles, highlighting phenomena such as harmonic generation and shock wave formation. A detailed discussion on the numerical modelling of ultrasonic systems follows, covering linear and nonlinear approaches, boundary conditions, and the challenges of accurately simulating cavitating systems. The review concludes with an analysis of recent developments, emerging trends, and future directions in computational modelling for ultrasonic applications. By presenting a structured overview of both the theoretical and practical aspects of ultrasonic wave propagation, this work aims to provide a foundation for future research and design improvements in sonochemical and acoustic systems.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107163"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on optimization of extraction and purification processes for total flavonoids from Lycopi herba roots and their anti-proliferative effects on fibrous synoviocytes in human rheumatoid arthritis","authors":"Jie Chen ,&nbsp;Chunyang Jiang ,&nbsp;Zhenyu Liu ,&nbsp;Panpan Wang ,&nbsp;Qiang Ma ,&nbsp;Nong Zhou","doi":"10.1016/j.ultsonch.2024.107164","DOIUrl":"10.1016/j.ultsonch.2024.107164","url":null,"abstract":"<div><div><em>Lycopi herba</em>, a traditional Chinese medicinal plant, has long been valued for its aerial parts. however, its roots, which are often discarded as non-medicinal waste, actually contain flavonoid compounds that possess potential medicinal values such as anti-inflammatory, antioxidant, and anti-tumor activities. Despite this, studies on the extraction, purification, and biological activity assessment of total flavonoids from <em>L. herba</em> roots (TFLHR) remain inadequate. Our study aimed to optimize the extraction and purification processes for TFLHR and evaluate their anti-proliferative effects on human fibroblast-like synoviocytes (HFLS-RA), which are key pathological cells in rheumatoid arthritis. By utilizing ultrasound-assisted extraction combined with response surface methodology (RSM), we optimized the extraction conditions, achieving a total flavonoid content of 90.484 ± 0.974 mg/g under the optimal settings: a liquid–solid ratio of 48:1 mL/g, 13 min of ultrasound treatment, 70 % ethanol, and an extraction temperature of 43°C. Subsequently, macroporous resin chromatography was employed for flavonoid purification, with AB-8 resin exhibiting the highest performance, achieving adsorption and desorption rates of 79.64 ± 1.51 % and 88.61 ± 1.02 %, respectively. By further refining the purification conditions through RSM, the purity of flavonoids was increased to 63.9 ± 1.86 %. Through ultra performance liquid chromatography tandem-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) analysis, 74 flavonoid compounds across 15 categories were identified. Further activity studies demonstrated that purified TFLHR exhibited significant concentration-dependent anti-proliferative effects on HFLS-RA cells. This study not only provides a scientific basis for the comprehensive utilization of <em>L. herba</em> root resources but also highlights the potential medicinal value of TFLHR in the treatment of rheumatoid arthritis, laying a foundation for future research into its specific mechanisms and clinical applications.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107164"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142684423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental and numerical research on jet dynamics of cavitation bubble near dual particles","authors":"Yuning Zhang ,&nbsp;Xuan Lu ,&nbsp;Jinsen Hu ,&nbsp;Jiaxin Yu ,&nbsp;Yuning Zhang","doi":"10.1016/j.ultsonch.2024.107168","DOIUrl":"10.1016/j.ultsonch.2024.107168","url":null,"abstract":"<div><div>The current paper delves into the jet dynamics arising from a cavitation bubble in proximity to a dual-particle system, employing both experimental methodology and numerical simulation. The morphological development of a laser-induced bubble as well as the production of jets are captured by utilizing high-speed photography. The principles of bubble morphology evolution and jet formation are revealed by a OpenFOAM solver, which takes into account the effects of two-phase fluid compressibility, phase changes, heat transfer, and surface tension. Fluid temperature variations induced by bubble oscillations are discussed. The results indicate that the jet dynamics can be categorized into three cases, i.e. bubble-splitting double jets, impacting single jet, non-impacting double jets. For bubble-splitting double jets, bubble splitting is induced by an annular pressure gradient towards the bubble axis. This resulted in the production of two unequal-sized sub-bubbles, which subsequently produced double jets in opposite directions. The fluid temperature close to the bubble interface is low, while the bubble center is high. For impacting single jet, it is induced by a conical pressure gradient towards the nearest particle and the jet impacts the particle. The fluid temperature is low near the jet and high near the particle. When the jet penetrates the bubble interface, the temperature inside the bubble reaches its peak. For non-impacting double jets, they are induced by pressure gradients facing each other and they do not impact particles. The temperature inside the bubble increases with the proximity of the two jets.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107168"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142684421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the dynamic characteristics of the cavitation bubble collapsing between multiple particles","authors":"Xiaoyu Wang ,&nbsp;Jingrong Hu ,&nbsp;Yufei Wang ,&nbsp;Yuning Zhang ,&nbsp;Yuning Zhang","doi":"10.1016/j.ultsonch.2024.107169","DOIUrl":"10.1016/j.ultsonch.2024.107169","url":null,"abstract":"<div><div>The combined action of multiple particles and cavitation bubbles can severely damage hydraulic machinery. Combining the Kelvin impulse theory and the results of high-speed photography experiments, this paper researches the dynamic behaviors of a single bubble located between three equal-sized spherical particles. Non-spherical morphological evolution characteristics in the collapse stage of the bubble are described. The influence of the arrangement of the three particles on the direction and intensity of the bubble migration is quantitatively analyzed. On this basis, the spatial distribution characteristics of the zero impulse points with the Kelvin impulse equal to zero are explored. The results show that: (1) As the bubble is induced in the symmetric positions, three typical cases of collapse characteristics are summarized according to the bubble morphology, including V-shaped, T-shaped, and ginkgo leaf-shaped. (2) As the bubble incipient position is shifted on the symmetry axis, the Kelvin impulse intensity shows a non-monotonic trend with its direction varying many times. Both the impulse intensity and direction are significantly affected by the arrangement of particles. (3) There are multiple zero impulse points among the three particles, and both the spatial location and the number of the zero impulse points are affected by the arrangement of the particles.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107169"},"PeriodicalIF":8.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142684485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the effect and mechanism of ultrasonic-assisted enzymolysis on antioxidant peptide activity in walnuts","authors":"Jiaying Huo ,&nbsp;Zhaowei Cui ,&nbsp;Ruru Zhang ,&nbsp;Hui Ouyang ,&nbsp;Xiaolong Liu ,&nbsp;Ping Wang ,&nbsp;Xiongwei Yu ,&nbsp;Tingting Xie ,&nbsp;Sihai Gao ,&nbsp;Shugang Li","doi":"10.1016/j.ultsonch.2024.107159","DOIUrl":"10.1016/j.ultsonch.2024.107159","url":null,"abstract":"<div><div>Walnut meal is a large quantity and high-quality resource with great exploitation value. Ultrasonic-assisted enzymolysis (UAE) was utilized in the preparation of peptides from walnut meal protein. Results indicated that by optimizing the UAE process with neutral protease, an ultrasound power of 180 W, a 4.3 h duration and an enzyme dosage of 10 KU/g, the walnut peptides exhibited the most potent antioxidant activity. In comparison to the control group, the WPI treated with ultrasound and neutral enzymes in combination (UNWPI) demonstrated a significant enhancement in their DPPH, ABTS, and ·OH scavenging capabilities, with increases of 234.23 %, 240.22 %, and 69.52 %, respectively. By analyzing the structure of walnut antioxidant peptides with or without ultrasound, it was observed that the underlying mechanism for the increased antioxidant activity was that UAE not only formed more small peptides, but also produced more peptides with hydrophobic amino acids at their terminal ends. Subsequently, six peptides were identified and screened from UNWPI, namely IFW, IIPF, IVAF, IIFY, ILAFF, and IFIP, which exhibited high antioxidant activity and could bind to Keap1 protein through hydrogen bonding, π-alkyl interactions, and π-π stacking interactions. The research results provided theoretical basis and technical support for the preparation of walnut antioxidant peptides and the high-value utilization of walnut meal.</div></div>","PeriodicalId":442,"journal":{"name":"Ultrasonics Sonochemistry","volume":"112 ","pages":"Article 107159"},"PeriodicalIF":8.7,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142694977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}