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Utilizing OSA-modified starch with various molecular weights for flavonoid extraction from"Quzhiqiao"(immature fruit of Citrus paradisi'Changshan Huyou')
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作者 Lu Wang Xuyi Zhou +3 位作者 Shengmin Lu Siew Young Quek Juzhao Liu qi cui 《Beverage Plant Research》 2023年第1期280-286,共7页
In order to investigate the extraction efficiency of flavonoids by octenyl succinic acid-modified starch(OSA-modified starch)with varying molecular weights,the immature fruit of Citrus paradisi'Changshan Huyou'... In order to investigate the extraction efficiency of flavonoids by octenyl succinic acid-modified starch(OSA-modified starch)with varying molecular weights,the immature fruit of Citrus paradisi'Changshan Huyou',commonly known as"Quzhiqiao",was used as the extraction target in this research.OSA-modified starch was successfully identified and refined,ensuring its molecular weight was appropriate and extraction was optimized.The experimental findings suggested that a concentration of 20 mg/mL of medium molecular weight gelatinized OSA-modified starch was optimal for extracting flavonoids from"Quzhiqiao"using an ultrasound-assisted method(1,000 W,40 min).Additionally,the ratio of the mass of"Quzhiqiao"to the volume of gelatinized OSA-modified starch employed in this process was determined to be 15 mg/mL.The findings from the in vitro antioxidant studies indicated significant variations in the antioxidant activities of the extract solutions of OSA-modified starches with varying molecular weights.These differences can potentially be attributed to substantial variations in the extract solutions composition. 展开更多
关键词 WEIGHTS STARCH modified
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Casein kinase-2 inhibition promotes retinal ganglion cell survival after acute intraocular pressure elevation
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作者 Meng Wang Shi-qi Yao +8 位作者 Yao Huang Jia-Jian Liang Yanxuan Xu Shaowan Chen Yuhang Wang Tsz Kin Ng Wai Kit Chu qi cui Ling-Ping Cen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1112-1118,共7页
Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma,the leading cause of irreversible blindness.We previously demonstrated that casein kinase-2... Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma,the leading cause of irreversible blindness.We previously demonstrated that casein kinase-2 inhibition can promote retinal ganglion cell survival and axonal regeneration in rats after optic nerve injury.To investigate the underlying mechanism,in the current study we increased the intraocular pressure of adult rats to 75 mmHg for 2 hours and then administered a casein kinase-2 inhibitor(4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole)by intravitreal injection.We found that intravitreal injection of 4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole promoted retinal ganglion cell survival and reduced the number of infiltrating macrophages.Transcriptomic analysis showed that the mitogen activated protein kinase signaling pathway was involved in the response to intraocular pressure elevation but was not modulated by the casein kinase-2 inhibitors.Furthermore,casein kinase-2 inhibition downregulated the expression of genes(Cck,Htrsa,Nef1,Htrlb,Prph,Chat,Slc18a3,Slc5a7,Scn1b,Crybb2,Tsga10ip,and Vstm21)involved in intraocular pressure elevation.Our data indicate that inhibition of casein kinase-2 can enhance retinal ganglion cell survival in rats after acute intraocular pressure elevation via macrophage inactivation. 展开更多
关键词 casein kinase-2 GLAUCOMA intraocular pressure elevation MACROPHAGES retinal ganglion cells
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干眼患者泪液结晶图和脂质层异常的关系研究 被引量:6
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作者 姚涛 崔琦 何伟 《国际眼科杂志》 CAS 北大核心 2020年第7期1279-1282,共4页
目的:评估干眼患者泪液结晶图中外层透明带的临床意义,探索评估泪液脂质层的新方法。方法:随机选取2018-05/2019-07于在我院就诊的干眼患者47例47眼(均取右眼数据进行分析),所有入组患者均行眼表疾病指数(OSDI)问卷评分,采用DR-1泪膜干... 目的:评估干眼患者泪液结晶图中外层透明带的临床意义,探索评估泪液脂质层的新方法。方法:随机选取2018-05/2019-07于在我院就诊的干眼患者47例47眼(均取右眼数据进行分析),所有入组患者均行眼表疾病指数(OSDI)问卷评分,采用DR-1泪膜干涉成像仪行脂质层分级检测,眼表综合分析仪行非侵入式泪膜破裂时间(NIBUT)和泪河高度检查,采集泪液行泪液结晶试验,拍摄泪液结晶图全貌,使用Digimizer软件测量结晶图,计算结晶图外层透明带的面积占比,并分析其与OSDI评分、脂质层分级、泪河高度、NIBUT的相关性。结果:本研究纳入患者泪液结晶图透明带面积占比与OSDI评分呈负相关(r=-0.764,P<0.05),与DR-1成像仪脂质层分级呈负相关(r=-0.838,<0.05),与NIBUT呈正相关(r=0.575,P<0.05),与泪河高度无明显相关(r=-0.237,P=0.112)。结论:检测泪液结晶图外层透明带可有效评估泪液脂质层情况,透明带面积占比越大,脂质层越厚。该检测方法具有结果可量化、重复性较好、设备要求低等优点。 展开更多
关键词 干眼 泪膜脂质层 泪液结晶试验 眼表疾病指数 泪河高度
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球囊扩张式支架治疗症状性颅内动脉狭窄的临床应用 被引量:2
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作者 丁健 齐翠 +4 位作者 彭丽静 胡效坤 孙玉杰 马祥坤 张勇 《医学影像学杂志》 2018年第4期542-545,共4页
目的探讨球囊扩张式支架治疗症状性颅内动脉粥样硬化性狭窄围手术期的安全性及有效性。方法分析药物治疗无效而选择球扩式支架置入治疗的颅内动脉重度狭窄患者38例临床和影像学资料,分析颅内动脉狭窄形态、技术成功率、围手术期并发症... 目的探讨球囊扩张式支架治疗症状性颅内动脉粥样硬化性狭窄围手术期的安全性及有效性。方法分析药物治疗无效而选择球扩式支架置入治疗的颅内动脉重度狭窄患者38例临床和影像学资料,分析颅内动脉狭窄形态、技术成功率、围手术期并发症、临床及影像随访结果。结果 1)本组患者支架成形术的技术成功率为97.36%,术后平均狭窄率(88.27±5.242)%下降至(11.24±4.36)%;2)所有患者进行30天围手术期随访观察,其中1例术中发生蛛网膜下腔出血,1例术中急性支架内血栓形成。结论球扩式支架治疗重度症状性颅内动脉粥样硬化性狭窄的技术成功率高,治疗相对安全,短期疗效较好。 展开更多
关键词 动脉粥样硬化 颅内动脉狭窄 球囊扩张式支架
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Identifying Materials of Photographic Images and Photorealistic Computer Generated Graphics Based on Deep CNNs 被引量:15
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作者 qi cui Suzanne McIntosh Huiyu Sun 《Computers, Materials & Continua》 SCIE EI 2018年第5期229-241,共13页
Currently,some photorealistic computer graphics are very similar to photographic images.Photorealistic computer generated graphics can be forged as photographic images,causing serious security problems.The aim of this... Currently,some photorealistic computer graphics are very similar to photographic images.Photorealistic computer generated graphics can be forged as photographic images,causing serious security problems.The aim of this work is to use a deep neural network to detect photographic images(PI)versus computer generated graphics(CG).In existing approaches,image feature classification is computationally intensive and fails to achieve realtime analysis.This paper presents an effective approach to automatically identify PI and CG based on deep convolutional neural networks(DCNNs).Compared with some existing methods,the proposed method achieves real-time forensic tasks by deepening the network structure.Experimental results show that this approach can effectively identify PI and CG with average detection accuracy of 98%. 展开更多
关键词 Image identification CNN DNN DCNNs computer generated graphics
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Mechanisms of secondary degeneration after partial optic nerve transection 被引量:7
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作者 Hong-Ying Li Yi-Wen Ruan +2 位作者 Chao-Ran Ren qi cui Kwok-Fai So 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第6期565-574,共10页
Secondary degeneration occurs commonly in the central nervous system after traumatic injuries and following acute and chronic diseases, including glaucoma. A constellation of mechanisms have been shown to be associate... Secondary degeneration occurs commonly in the central nervous system after traumatic injuries and following acute and chronic diseases, including glaucoma. A constellation of mechanisms have been shown to be associated with secondary degeneration including apoptosis, necrosis, autophagy, oxidative stress, excitotoxicity, derangements in ionic homeostasis and calcium influx. Glial cells, such as microglia, astrocytes and oligodendrocytes, have also been demon- strated to take part in the process of secondary injury. Partial optic nerve transection is a useful model which was established about 13 years ago. The merit of this model compared with other optic nerve injury models used for glaucoma study, including complete optic nerve transection model and optic nerve crush model, is the possibility to separate primary degeneration from secondary degeneration in location. Therefore, it provides a good tool for the study of secondary degeneration. This review will focus on the research progress of the mechanisms of secondary degeneration using partial optic nerve transection model. 展开更多
关键词 secondary degeneration partial injury optic nerve oxidative stress EXCITOTOXICITY calci-um overload MITOCHONDRION macrophage ASTROCYTE OLIGODENDROCYTE
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Withaferin A inhibits ferroptosis and protects against intracerebral hemorrhage 被引量:6
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作者 Zi-Xian Zhou qi cui +8 位作者 Ying-Mei Zhang Jia-Xin Yang Wen-Jing Xiang Ning Tian Yan-Lin Jiang Mei-Ling Chen Bin Yang qing-Hua Li Ru-Jia Liao 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1308-1315,共8页
Recent studies have indicated that suppressing oxidative stress and ferroptosis can considerably improve the prognosis of intracerebral hemorrhage(ICH).Withaferin A(WFA),a natural compound,exhibits a positive effect o... Recent studies have indicated that suppressing oxidative stress and ferroptosis can considerably improve the prognosis of intracerebral hemorrhage(ICH).Withaferin A(WFA),a natural compound,exhibits a positive effect on a number of neurological diseases.However,the effects of WFA on oxidative stress and ferroptosis-mediated signaling pathways to ICH remain unknown.In this study,we investigated the neuroprotective effects and underlying mechanism for WFA in the regulation of ICH-induced oxidative stress and ferroptosis.We established a mouse model of ICH by injection of autologous tail artery blood into the caudate nucleus and an in vitro cell model of hemin-induced ICH.WFA was injected intracerebroventricularly at 0.1,1 or 5μg/kg once daily for 7 days,starting immediately after ICH operation.WFA markedly reduced brain tissue injury and iron deposition and improved neurological function in a dose-dependent manner 7 days after cerebral hemorrhage.Through in vitro experiments,cell viability test showed that WFA protected SH-SY5Y neuronal cells against hemin-induced cell injury.Enzyme-linked immunosorbent assays in vitro and in vivo showed that WFA markedly decreased the level of malondialdehyde,an oxidative stress marker,and increased the activities of anti-oxidative stress markers superoxide dismutase and glutathione peroxidase after ICH.Western blot assay,quantitative polymerase chain reaction and immunofluorescence results demonstrated that WFA activated the nuclear factor E2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)signaling axis,promoted translocation of Nrf2 from the cytoplasm to nucleus,and increased HO-1 expression.Silencing Nrf2 with siRNA completely reversed HO-1 expression,oxidative stress and protective effects of WFA.Furthermore,WFA reduced hemin-induced ferroptosis.However,after treatment with an HO-1 inhibitor,the neuroprotective effects of WFA against hemin-induced ferroptosis were weakened.MTT test results showed that WFA combined with ferrostatin-1 reduced hemin-induced SH-SY5Y neuronal cell injury.Our findings reveal that WFA treatment alleviated ICH injury-induced ferroptosis and oxidative stress through activating the Nrf2/HO-1 pathway,which may highlight a potential role of WFA for the treatment of ICH. 展开更多
关键词 behavior brain injuries hemorrhagic stroke ferroptosis heme oxygenase-1 NEUROPROTECTION nuclear factor E2-related factor 2 nuclear translocator oxidative stress STROKE
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Effect of surface treatment for aluminum foils on discharge properties of lithium-ion battery 被引量:4
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作者 Shigeki NAKANISHI Takashi SUZUKI +2 位作者 qi cui Jun AKIKUSA Kenzo NAKAMURA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2314-2319,共6页
Aluminum foils having thicknesses of 10-20 μm are commonly employed as current collectors for cathode electrodes in Li-ion batteries. The effects of the surface morphology of the foil on battery performance were inve... Aluminum foils having thicknesses of 10-20 μm are commonly employed as current collectors for cathode electrodes in Li-ion batteries. The effects of the surface morphology of the foil on battery performance were investigated by using a foil with roughened surface by chemical etching and a plain foil with smooth surface on both sides. For high-conductivity LiCoO2 active materials with large particle size, there are no significant differences in battery performance between the two types of foils. But for low-conductivity LiFePO4 active materials with small particle size, high-rate discharge properties are significantly different. The possibility shows that optimizing both the surface morphology of the aluminum foil and particle size of active material leads to improvement of the battery performance. 展开更多
关键词 lithium-ion battery battery performance surface treatment CONDUCTIVITY plain foil roughened foil
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Clinical efficacy of transjugular intrahepatic portosystemic shunt created through left or right branches of the portal vein:A meta-analysis 被引量:3
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作者 Shaobo Zhai qi cui +3 位作者 Fang Dong Shiqi Wen Moubo Si Quan Chen 《Journal of Interventional Medicine》 2021年第4期190-196,共7页
Background and aim:Transjugular intrahepatic portosystemic shunt(TIPS)is a technique successfully used to treat portal hypertension and its complications.However,the choice of the branch,left(L)or right(R),of the port... Background and aim:Transjugular intrahepatic portosystemic shunt(TIPS)is a technique successfully used to treat portal hypertension and its complications.However,the choice of the branch,left(L)or right(R),of the portal vein resulting in a better outcome is still under debate.Therefore,this meta-analysis aims to evaluate which branch has a better curative effect on patients treated with TIPS.Methods:PubMed,EMBASE,Web of science,Cochrane Library databases,Wanfang database and CBM were used for our search in October 2019 and updated in June 2021.The following parameters were used in evaluation:overall mortality,hepatic encephalopathy,shunt dysfunction,variceal rebleeding and rate of postoperative ascites.Results:There were seven studies included.The sample size was 1940.A lower risk of mortality was observed in TIPS-L-treated patients compared with TIPS-R-treated ones(OR=0.65,95%CI=0.50-0.85,p=0.002).A lower risk of shunt dysfunction was observed in TIPS-L-treated patients compared with TIPS-R-treated ones(OR=0.53,95%CI=0.33-0.87,p=0.01).And the TIPS-L group had a significantly higher hepatic encephalopathy-free rate than the TIPS-R group(OR=0.59,95%CI=0.44-0.78,p=0.0002).However,the rate of rebleeding(OR=0.75,95%CI=0.55-1.03,p=0.07)and incidence of postoperative ascites(OR=1.14,95%CI=0.86-1.51,p=0.38)was not statistically significant between the two groups.Conclusions:Based on the currently available evidence,the technique of TIPS through the left branch of the portal vein can significantly reduce the occurrence of overall postoperative mortality,hepatic encephalopathy and shunt dysfunction. 展开更多
关键词 META-ANALYSIS Transjugular intrahepatic portosystemic shunt Portal hypertension Overall mortality Hepatic encephalopathy Shunt dysfunction
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A Novel Steganography Scheme Combining Coverless Information Hiding and Steganography 被引量:5
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作者 Ruohan Meng Zhili Zhou +2 位作者 qi cui Xingming Sun Chengsheng Yuan 《Journal of Information Hiding and Privacy Protection》 2019年第1期43-48,共6页
At present,the coverless information hiding has been developed.However,due to the limited mapping relationship between secret information and feature selection,it is challenging to further enhance the hiding capacity ... At present,the coverless information hiding has been developed.However,due to the limited mapping relationship between secret information and feature selection,it is challenging to further enhance the hiding capacity of coverless information hiding.At the same time,the steganography algorithm based on object detection only hides secret information in foreground objects,which contribute to the steganography capacity is reduced.Since object recognition contains multiple objects and location,secret information can be mapped to object categories,the relationship of location and so on.Therefore,this paper proposes a new steganography algorithm based on object detection and relationship mapping,which integrates coverless information hiding and steganography.In this method,the coverless information hiding is realized by mapping the object type,color and secret information in object detection method.At the same time,the object detection method is used to find the safe area to hide secret messages.The proposed algorithm can not only improve the steganographic capacity of the two information hiding methods but also make the coverless information hiding more secure and robust. 展开更多
关键词 STEGANOGRAPHY faster R-CNN coverless information hiding
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Effects of low level laser treatment on the survival of axotomized retinal ganglion cells in adult Hamsters 被引量:1
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作者 Kwok-Fai So Mason Chin Pang Leung qi cui 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第21期1863-1869,共7页
Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents l... Injury to axons close to the neuronal bodies in the mammalian central nervous system causes a large proportion of parenting neurons to degenerate. It is known that optic nerve transection close to the eye in rodents leads to a loss of about half of retinal ganglion cells in 1 week and about 90% in 2 weeks. Using low level laser treatment in the present study, we demonstrated that treatment with helium-neon (660 nm) laser with 15 mW power could delay retinal ganglion cell death after optic nerve axotomy in adult hamsters. The effect was most apparent in the ifrst week with a short period of treatment time (5 minutes) in which 65–66% of retinal ganglion cells survived the optic nerve axotomy whereas 45–47% of retinal ganglion cells did so in optic nerve axotomy controls. We also found that single dose and early commencement of laser irradiation were important in protecting retinal ganglion cells following optic nerve axotomy. These ifndings thus convincingly show that appropriate laser treatment may be neuroprotective to retinal gan-glion cells. 展开更多
关键词 low level laser treatment retinal ganglion cells optic nerve injury NEUROPROTECTION mi-croglial proliferation optic nerve axotomy
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A Novel Steganography Algorithm Based on Instance Segmentation 被引量:1
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作者 Ruohan Meng qi cui +2 位作者 Zhili Zhou Chengsheng Yuan Xingming Sun 《Computers, Materials & Continua》 SCIE EI 2020年第4期183-196,共14页
Information hiding tends to hide secret information in image area where is rich texture or high frequency,so as to transmit secret information to the recipient without affecting the visual quality of the image and aro... Information hiding tends to hide secret information in image area where is rich texture or high frequency,so as to transmit secret information to the recipient without affecting the visual quality of the image and arousing suspicion.We take advantage of the complexity of the object texture and consider that under certain circumstances,the object texture is more complex than the background of the image,so the foreground object is more suitable for steganography than the background.On the basis of instance segmentation,such as Mask R-CNN,the proposed method hides secret information into each object's region by using the masks of instance segmentation,thus realizing the information hiding of the foreground object without background.This method not only makes it more efficient for the receiver to extract information,but also proves to be more secure and robust by experiments. 展开更多
关键词 STEGANOGRAPHY object detection mask R-CNN irregular region
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Efficient,rapid and incremental extraction of bioactive compounds from the flowers of Hibiscus manihot L. 被引量:1
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作者 Juzhao Liu Yujie Fu qi cui 《Beverage Plant Research》 2023年第1期93-100,共8页
Flavonoids are the primary functional components in the flowers of Hibiscus manihot L.(HMLF).In this study,an efficient and green ionic liquid-high-speed homogenization coupled with microwave-assisted extraction(IL-HS... Flavonoids are the primary functional components in the flowers of Hibiscus manihot L.(HMLF).In this study,an efficient and green ionic liquid-high-speed homogenization coupled with microwave-assisted extraction(IL-HSH-MAE)technique was firstly established and implemented to extract seven target flavonoids from HMLF.Single-factor experiments and Box-Behnken design(BBD)were utilized to maximize the extraction conditions of IL-HSH-MAE,which were as follows:0.1 M of[C4mim]Br,homogenate speed of 7,000 rpm,homogenate time of 120 s,liquid/solid ratio of 24 mL/g,extraction temperature of 62℃and extraction time of 15 min.The maximal total extraction yield of seven target flavonoids attained 22.04 mg/g,which was considerably greater than the yields obtained by IL-HSH,IL-MAE,60%ethanol-HSH-MAE and 60%ethanol-MAE.These findings suggested that the IL-HSH-MAE method can be exploited as a rapid and efficient approach for extracting natural products from plants.The process also possesses outstanding superiority in being environmentally friendly and having a high extraction efficiency and is expected to be a luciferous prospect extraction technology. 展开更多
关键词 INCREMENTAL utilized MAXIMAL
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A Survey of Image Information Hiding Algorithms Based on Deep Learning
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作者 Ruohan Meng qi cui Chengsheng Yuan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第12期425-454,共30页
With the development of data science and technology,information security has been further concerned.In order to solve privacy problems such as personal privacy being peeped and copyright being infringed,information hi... With the development of data science and technology,information security has been further concerned.In order to solve privacy problems such as personal privacy being peeped and copyright being infringed,information hiding algorithms has been developed.Image information hiding is to make use of the redundancy of the cover image to hide secret information in it.Ensuring that the stego image cannot be distinguished from the cover image,and sending secret information to receiver through the transmission of the stego image.At present,the model based on deep learning is also widely applied to the field of information hiding.This paper makes an overall conclusion on image information hiding based on deep learning.It is divided into four parts of steganography algorithms,watermarking embedding algorithms,coverless information hiding algorithms and steganalysis algorithms based on deep learning.From these four aspects,the state-of-the-art information hiding technologies based on deep learning are illustrated and analyzed. 展开更多
关键词 STEGANOGRAPHY DEEP learning STEGANALYSIS WATERMARKING coverless information hiding.
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High pressure synthesis and characterization of the pyrochlore Dy2Pt2O7:A new spin ice material
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作者 qi cui Yun-qi Cai +5 位作者 Xiang Li Zhi-Ling Dun Pei-Jie Sun Jian-Shi Zhou Hai-Dong Zhou Jin-Guang Cheng 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期116-120,共5页
The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K.We found that ... The cubic pyrochlore Dy2Pt2O7 was synthesized under 4 GPa and 1000℃ and its magnetic and thermodynamic properties were characterized by DC and AC magnetic susceptibility and specific heat down to 0.1 K.We found that Dy2Pt2O7 does not form long-range magnetic order,but displays characteristics of canonical spin ice such as Dy2Pt2O7,including(1)a large effective moment 9.64μB close to the theoretical value and a small positive Curie-Weiss temperatureθCW=+0.77 K signaling a dominant ferromagnetic interaction among the Ising spins;(2)a saturation moment ~4.5μB being half of the total moment due to the local<111>Ising anisotropy;(3)thermally activated spin relaxation behaviors in the low(~1 K)and high(~20 K)temperature regions with different energy barriers and characteristic relaxation time;and most importantly,(4)the presence of a residual entropy close to Pauling’s estimation for water ice. 展开更多
关键词 Dy2Pt2O7 PYROCHLORE OXIDE SPIN ICE high-pressure synthesis
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A density-wave-like transition in the polycrystalline V_(3)Sb_(2) sample with bilayer kagome lattice
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作者 Ningning Wang Yuhao Gu +13 位作者 M.A.McGuire Jiaqiang Yan Lifen Shi qi cui Keyu Chen Yuxin Wang Hua Zhang Huaixin Yang Xiaoli Dong Kun Jiang Jiangping Hu Bosen Wang Jianping Sun Jinguang Cheng 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期15-23,共9页
Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties o... Recently,transition-metal-based kagome metals have aroused much research interest as a novel platform to explore exotic topological quantum phenomena.Here we report on the synthesis,structure,and physical properties of a bilayer kagome lattice compound V_(3)Sb_(2).The polycrystalline V_(3)Sb_(2) samples were synthesized by conventional solid-state-reaction method in a sealed quartz tube at temperatures below 850℃.Measurements of magnetic susceptibility and resistivity revealed consistently a density-wave-like transition at Tdw≈160 K with a large thermal hysteresis,even though some sample-dependent behaviors were observed presumably due to the different preparation conditions.Upon cooling through Tdw,no strong anomaly in lattice parameters and no indication of symmetry lowering were detected in powder x-ray diffraction measurements.This transition can be suppressed completely by applying hydrostatic pressures of about 1.8 GPa,around which no sign of superconductivity was observed down to 1.5 K.Specific-heat measurements revealed a relatively large Sommerfeld coefficientγ=18.5 mJ·mol^(-1)·K^(-2),confirming the metallic ground state with moderate electronic correlations.Density functional theory calculations indicate that V_(3)Sb_(2) shows a non-trivial topological crystalline property.Thus,our study makes V_(3)Sb_(2) a new candidate of metallic kagome compound to study the interplay between density-wave-order,nontrivial band topology,and possible superconductivity. 展开更多
关键词 V_(3)Sb_(2) kagome metal charge density wave pressure effect
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Speech Encryption with Fractional Watermark
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作者 Yan Sun Cun Zhu qi cui 《Computers, Materials & Continua》 SCIE EI 2022年第10期1817-1825,共9页
Research on the feature of speech and image signals are carried out from two perspectives,the time domain and the frequency domain.The speech and image signals are a non-stationary signal,so FT is not used for the non... Research on the feature of speech and image signals are carried out from two perspectives,the time domain and the frequency domain.The speech and image signals are a non-stationary signal,so FT is not used for the non-stationary characteristics of the signal.When short-term stable speech is obtained by windowing and framing the subsequent processing of the signal is completed by the Discrete Fourier Transform(DFT).The Fast Discrete Fourier Transform is a commonly used analysis method for speech and image signal processing in frequency domain.It has the problem of adjusting window size to a for desired resolution.But the Fractional Fourier Transform can have both time domain and frequency domain processing capabilities.This paper performs global processing speech encryption by combining speech with image of Fractional Fourier Transform.The speech signal is embedded watermark image that is processed by fractional transformation,and the embedded watermark has the effect of rotation and superposition,which improves the security of the speech.The paper results show that the proposed speech encryption method has a higher security level by Fractional Fourier Transform.The technology is easy to extend to practical applications. 展开更多
关键词 Fractional Fourier Transform WATERMARK speech signal processing image processing
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Critical behavior and effect of Sr substitution in double perovskite Ca2CrSbO6
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作者 Yuan-Yuan Jiao Jian-Ping Sun qi cui 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第3期454-460,共7页
The double perovskite Ca2CrSbO6 exhibits a ferromagnetic long-range order below Tc=13 K and a saturation magnetization of 2.35µB at 2 K.In this study,the polycrystalline Ca2CrSbO6 is synthesized under high pressu... The double perovskite Ca2CrSbO6 exhibits a ferromagnetic long-range order below Tc=13 K and a saturation magnetization of 2.35µB at 2 K.In this study,the polycrystalline Ca2CrSbO6 is synthesized under high pressure and high temperature,and the critical behavior of the ferromagnetic material as well as the effects of the magnetic behavior due to the isovalent substitution of Sr2+for Ca2+is investigated.Also studied are the ferromagnetic criticality of the double perovskite Ca2CrSbO6 at the ferromagnetic transition temperature Tc≈12.6 K from the isotherms of magnetization M(H)via an iteration process and the Kouvel–Fisher method.The critical exponents associated with the transition are determined as follows:β=0.322,γ=1.241,andδ=4.84.The magnetization data in the vicinity of Tc can be scaled into two universal curves in the plot of M/|ε|βversus H/|ε|β+γ,whereε=T/Tc−1.The obtainedβandγvalues are consistent with the predicted values from a three-dimensional Ising model.The effects of Sr substitution on the double perovskite Ca2CrSbO6 are taken into consideration.As the Sr content increases,the(Ca2−xSrx)CrSbO6 polycrystal shows a continuous switch from ferromagnetic to antiferromagnetic behavior. 展开更多
关键词 high-temperature and high-pressure synthesis FERROMAGNET Ca2CrSbO6
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3D Object Detection with Attention:Shell-Based Modeling
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作者 Xiaorui Zhang Ziquan Zhao +1 位作者 Wei Sun qi cui 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期537-550,共14页
LIDAR point cloud-based 3D object detection aims to sense the surrounding environment by anchoring objects with the Bounding Box(BBox).However,under the three-dimensional space of autonomous driving scenes,the previou... LIDAR point cloud-based 3D object detection aims to sense the surrounding environment by anchoring objects with the Bounding Box(BBox).However,under the three-dimensional space of autonomous driving scenes,the previous object detection methods,due to the pre-processing of the original LIDAR point cloud into voxels or pillars,lose the coordinate information of the original point cloud,slow detection speed,and gain inaccurate bounding box positioning.To address the issues above,this study proposes a new two-stage network structure to extract point cloud features directly by PointNet++,which effectively preserves the original point cloud coordinate information.To improve the detection accuracy,a shell-based modeling method is proposed.It roughly determines which spherical shell the coordinates belong to.Then,the results are refined to ground truth,thereby narrowing the localization range and improving the detection accuracy.To improve the recall of 3D object detection with bounding boxes,this paper designs a self-attention module for 3D object detection with a skip connection structure.Some of these features are highlighted by weighting them on the feature dimensions.After training,it makes the feature weights that are favorable for object detection get larger.Thus,the extracted features are more adapted to the object detection task.Extensive comparison experiments and ablation experiments conducted on the KITTI dataset verify the effectiveness of our proposed method in improving recall and precision. 展开更多
关键词 3D object detection autonomous driving point cloud shell-based modeling self-attention mechanism
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Multi-Path Attention Inverse Discrimination Network for Offline Signature Verification
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作者 Xiaorui Zhang Yingying Wang +2 位作者 Wei Sun qi cui Xindong Wei 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3057-3071,共15页
Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other... Signature verification,which is a method to distinguish the authenticity of signature images,is a biometric verification technique that can effectively reduce the risk of forged signatures in financial,legal,and other business envir-onments.However,compared with ordinary images,signature images have the following characteristics:First,the strokes are slim,i.e.,there is less effective information.Second,the signature changes slightly with the time,place,and mood of the signer,i.e.,it has high intraclass differences.These challenges lead to the low accuracy of the existing methods based on convolutional neural net-works(CNN).This study proposes an end-to-end multi-path attention inverse dis-crimination network that focuses on the signature stroke parts to extract features by reversing the foreground and background of signature images,which effectively solves the problem of little effective information.To solve the problem of high intraclass variability of signature images,we add multi-path attention modules between discriminative streams and inverse streams to enhance the discriminative features of signature images.Moreover,a multi-path discrimination loss function is proposed,which does not require the feature representation of the samples with the same class label to be infinitely close,as long as the gap between inter-class distance and the intra-class distance is bigger than the set classification threshold,which radically resolves the problem of high intra-class difference of signature images.In addition,this loss can also spur the network to explore the detailed infor-mation on the stroke parts,such as the crossing,thickness,and connection of strokes.We respectively tested on CEDAR,BHSig-Bengali,BHSig-Hindi,and GPDS Synthetic datasets with accuracies of 100%,96.24%,93.86%,and 83.72%,which are more accurate than existing signature verification methods.This is more helpful to the task of signature authentication in justice and finance. 展开更多
关键词 Offline signatures biometric verification multi-path discrimination loss attention mechanisms inverse discrimination
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