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Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

《信息与电子工程前沿（英文）》 2015年 第16卷 第4期   页码 301-310 doi: 10.1631/FITEE.1400205

摘要： Quadrature demodulation is used in medical ultrasound imaging to derive the envelope and instantaneous phase of the received radio-frequency (RF) signal. In quadrature demodulation, RF signal is multiplied with the sine and cosine wave reference signal and then low-pass filtered to produce the base-band complex signal, which has high computational complexity. In this paper, we propose an efficient quadrature demodulation method for B-mode and color flow imaging, in which the RF signal is demodulated by a pair of finite impulse response filters without mixing with the reference signal, to reduce the computational complexity. The proposed method was evaluated with simulation and in vivo experiments. From the simulation results, the proposed quadrature demodulation method produced similar normalized residual sum of squares (NRSS) and velocity profile compared with the conventional quadrature demodulation method. In the in vivo color flow imaging experiments, the time of the demodulation process was 5.66 ms and 3.36 ms, for the conventional method and the proposed method, respectively. These results indicated that the proposed method can maintain the performance of quadrature demodulation while reducing computational complexity.

关键词： B-mode ultrasound imaging     Color flow imaging     Quadrature demodulation     Finite impulse response filter    

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High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

《医学前沿（英文）》 2010年 第4卷 第3期   页码 294-302 doi: 10.1007/s11684-010-0092-8

摘要： High-intensity focused ultrasound (HIFU) is a technique to destroy tissue at depth within the body, selectively and without harming overlying and adjacent structures within the path of the beam because the ultrasonic intensity at the beam focus is much higher than that outside of the focus. Diagnostic ultrasound is the first imaging modality used for guiding HIFU ablation. In 1997, a patient with osteosarcoma was first successfully treated with ultrasound imaging-guided HIFU in Chongqing, China. Over the last decade, thousands of patients with uterine fibroids, liver cancer, breast cancer, pancreatic cancer, bone tumors, and renal cancer have been treated with ultrasound imaging-guided HIFU. Based on several research groups’ reports, as well as our ten-year clinical experience, we conclude that this technique is safe and effective in treating human solid tumors. HIFU is a promising technique. Most importantly, HIFU offers patients another alternative when those patients have no other treatment available.

关键词： high-intensity focused ultrasound (HIFU)     ultrasound imaging-guided HIFU (USgHIFU)     magnetic resonance imaging-guided HIFU (MRgHIFU)    

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超声检查对胎儿畸形的诊断分析

李华洁

《中国工程科学》 2014年 第16卷 第5期   页码 70-72

摘要：

探讨产前超声检查(B 超)诊断先天性胎儿畸形的声像图特征，为临床提供信息，对畸形胎儿及时终止妊娠。

关键词： 产科B超     胎儿畸形     胎儿畸形诊断率    

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naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomal cellular imaging

Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 61-75 doi: 10.1007/s11705-019-1862-8

摘要： Four new fluorescent sensors ( - ) based on the 4-amino-1,8-naphthalimide fluorophores ( ) have been synthesized based on the classical fluorophore-spacer-receptor model. These four compounds all gave rise to emission bands centred at 535 nm, which were found to be highly pH dependent, the emission being ‘switched on’ in acidic media, while being quenched due to PET from the amino moieties to the excited state of the at more alkaline pH. The luminescent pH dependence for these probes was found to be highly dependent on the substitution on the imide site, as well as the polyamine chain attached to the position 4-amino moiety. In the case of sensor the presence of the 4-amino-aniline dominated the pH dependent quenching. Nevertheless, at higher pH, PET quenching was also found to occur from the polyamine site. Hence, is better described as a receptor -spacer -fluorophore-spacer -receptor system, where the dominant PET process is due to (normally less favourable) ‘directional’ PET quenching from the 4-amino-aniline unit to the site. Similar trends and pH fluorescence dependences were also seen for and . These compounds were also tested for their imaging potential and toxicity against HeLa cells (using DRAQ5 as nuclear stain which does now show pH dependent changes in acidic and neutral pH) and the results demonstrated that these compounds have reduced cellular viability at moderately high concentrations (with IC values between ca. 8‒30 µmol∙L ), but were found to be suitable for intracellular pH determination at 1 µmol∙L concentrations, where no real toxicity was observed. This allowed us to employ these as lysosomal probes at sub-toxic concentrations, where the based emission was found to be pH depended, mirroring that seen in aqueous solution for , with the main fluorescence changes occurring within acidic to neutral pH.

关键词： sensors     pH     photoinduced electron transfer     cellular imaging     confocal microscopy    

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Ultrasonic linear motor using the L-B mode Langevin transducer with an exponential horn

SHI Shengjun, CHEN Weishan, LIU Junkao, ZHAO Xuetao

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 212-217 doi: 10.1007/s11465-008-0026-1

摘要： An ultrasonic linear motor is proposed and fabricated by using the longitudinal and bending vibration double mode bolt-clamped Langevin type transducer to meet high power and speed requirements in the aerospace and semiconductor ind

关键词： longitudinal     vibration     bolt-clamped     semiconductor     ultrasonic    

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土石坝SH 波地震反射成像 Article

Edward W. Woolery

《工程（英文）》 2018年 第4卷 第5期   页码 694-701 doi: 10.1016/j.eng.2018.08.009

摘要：

评价地下物性和地质特征成像（如断层、空洞、低速层等）是近地表地球物理学中的经典问题，这些问题通常会危害岩土工程，尤其对大型土石防洪坝这类高危结构物危害更大。在美国，由于大部分重要的基础设施在20 世纪初至20 世纪中叶设计建成，目前这些堤坝已处于设计寿命的末期，之前被人忽略的或者在设计建造过程中被认为无关紧要的细微缺陷将会对堤坝安全造成严重威胁。这些构造在高水动力条件下会加速薄弱区域的恶化，并破坏其长期完整性。仅用传统钻探技术解决大坝的相关问题通常存在不足（缺乏横向分辨率），过高的成本同样限制了钻探技术的发展。然而，有选择的岩土钻探技术与近地表地球物理相结合，尤其是对堤坝内部细小结构和地质基础条件成像方面的剪切波（shear-wave，SH 波）地震反射技术，可以有效地降低堤坝修复工程所需的成本。为支持上述观点，本文以美国中部两个防洪坝为例，对其原位组分和工程建设组分进行SH 波地震反射成像。

关键词： 地球物理     地震反射     剪切波     近地表     坝体安全    

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Synthesis and characterization of phosphotungstic acid/activated carbon as a novel ultrasound oxidative

Liyan LIU, Yu ZHANG, Wei TAN

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 422-427 doi: 10.1007/s11705-013-1353-2

摘要： Phosphotungstic acid/activated carbon (PTA/AC) catalysts with various AC sizes or PTA content have been synthesized and characterized by N physisorption, X-ray diffraction, Fourier transform infrared spectroscopy and temperature programmed desorption of ammonia. These catalysts were then evaluated in terms of the removal of dibenzothiophene (DBT) by ultrasound-assisted oxidative desulfurization process. The results showed that the DBT conversion obviously increased with the decrease of AC support size and the increase of PTA content. After supporting PTA on AC, the DBT conversion can be improved by 38.9% after ultrasound irradiation for 10 min. In addition, the stability tests of PTA/AC showed that the catalytic oxidative activity of PTA/AC was nearly kept constant after ultrasound irradiation for 20 min, which makes it a promising catalyst to use in ultrasound-assisted oxidative desulfurization process.

关键词： phosphotungstic acid     activated carbon     ultrasound-assisted oxidative desulfurization    

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Studies of ultrasound disintegration of residual sludge and its energy consumption in water treatment

SHEN Jinfeng, YIN Xuan, GU Heping, Lv Xiaoping

《化学科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 395-398 doi: 10.1007/s11705-007-0072-y

摘要： To investigate the influence of ultrasound pretreatment on sludge anaerobic digestion, the ultrasound disintegration of residual sludge in water treatment of petrochemical plant was studied, and the mechanisms of ultrasound and medium were introduced. Experimental results indicate that ultrasound cavitation induces the rise of sludge temperature, which improves ultrasound disintegration on sludge. U1trasound pretreatment can advance observably the quantity of chemical oxygen demand in sludge supernatant fluid (SCOD), which increases with ultrasound intensity and sonication time. The degree of ultrasound disintegration increases with the specific energy input. When the specific energy input is l0 000 kJ/kg of total dry solids, the degree of ultrasonic sludge disintegration reaches 40%.

关键词： specific     supernatant     petrochemical     ultrasound intensity     temperature    

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evaluation of renal function using diffusion weighted imaging and diffusion tensor imaging in type 2

null

《医学前沿（英文）》 2014年 第8卷 第4期   页码 471-476 doi: 10.1007/s11684-014-0365-8

摘要：

This work aims to estimate the value of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in detecting early-stage kidney injury in type 2 diabetic patients with normoalbuminuria (NAU) versus microalbuminuria (MAU) prospectively. A total of 30 T2DM patients with normal kidney function were recruited and assigned to the NAU group (n = 14) or MAU group (n= 16) according to 8 h overnight urinary albuminuria excretion rate (AER) results. A contemporary cohort of health check-up recipients were included as controls (n = 12). DWI and DTI scans were performed on bilateral kidney using SE single-shot EPI, and apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the renal parenchyma was determined from ADC and FA maps of the three groups. ADC and FA values were compared among the three groups. According to DWI with a b value of 400 s/mm2, the MAU and NAU groups showed significantly lowered mean ADC values compared with the healthy controls (P<0.01). The mean ADC in the MAU group [(2.22±0.07)×10–3 mm2/s] was slightly lower than that of the NAU group [(2.31±0.22)×10–3 mm2/s], but this difference was not statistically significant (P>0.05). The FA value in the MAU group was higher than that in the control group (0.45±0.07 vs. 0.39±0.03, P = 0.004) but did not differ from that in the NAU group (0.42±0.03) (P>0.05). ADC and FA values may be more sensitive than urine AER in reflecting early-stage kidney injury and, hence, may facilitate earlier detection and quantitative evaluation of kidney injury in T2DM patients. Combined evaluation of ADC and FA values may provide a better quantitative approach for identifying diabetic nephropathy at early disease stages.

关键词： type 2 diabetes mellitus     microalbuminuria     diffusion weighted imaging     diffusion tensor imaging     early-stage kidney injury    

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Using ultrasound to improve the sequential post-synthesis modification method for making mesoporous Y

Rongxin Zhang, Peinan Zhong, Hamidreza Arandiyan, Yanan Guan, Jinmin Liu, Na Wang, Yilai Jiao, Xiaolei Fan

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 275-287 doi: 10.1007/s11705-019-1905-1

摘要： Mesoporous Y zeolites were prepared by the sequential chemical dealumination (using chelating agents such as ethylenediaminetetraacetic acid, H EDTA, and citric acid aqueous solutions) and alkaline desilication (using sodium hydroxide, NaOH, aqueous solutions) treatments. Specifically, the ultrasound-assisted alkaline treatment (i.e., ultrasonic treatment) was proposed as the alternative to conventional alkaline treatments which are performed under hydrothermal conditions. In comparison with the hydrothermal alkaline treatment, the ultrasonic treatment showed the comparatively enhanced efficiency (with the reduced treatment time, i.e., 5 min vs. 30 min, all with 0.2 mol·L NaOH at 65°C) in treating the dealuminated Y zeolites for creating mesoporosity. For example, after the treatment of a dealuminated zeolite Y (using 0.1 mol·L H EDTA at 100°C for 6 h), the ultrasonic treatment produced the mesoporous zeolite Y with the specific external surface area ( ) of 160 m ·g and mesopore volume ( ) of 0.22 cm ·g , being slightly higher than that by the conventional method (i.e., = 128 m ·g and = 0.19 cm ·g ). The acidic property and catalytic activity (in catalytic cracking of -octane) of mesoporous Y zeolites obtained by the two methods were comparable. The ultrasonic desilication treatment was found to be generic, also being effective to treat the dealuminated Y zeolites by citric acid. Additionally, the first step of chemical dealumination treatment was crucial to enable the effective creation of mesopores in the parent Y zeolite (with a silicon-to-aluminium ratio, Si/Al= 2.6) regardless of the subsequent alkaline desilication treatment (i.e., ultrasonic or hydrothermal). Therefore, appropriate selection of the condition of the chemical dealumination treatment based on the property of parent zeolites, such as Si/Al ratio and crystallinity, is important for making mesoporous zeolites effectively.

关键词： zeolite Y     mesoporous zeolite     post-synthesis treatment     ultrasound     chemical dealumination treatment     alkaline desilication treatment    

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Ultrasound-mediated targeted microbubbles: a new vehicle for cancer therapy

Junxiao YE, Huining HE, Junbo GONG, Weibing DONG, Yongzhuo HUANG, Jianxin WANG, Guanyi CHEN, Victor C YANG

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 20-28 doi: 10.1007/s11705-013-1311-z

摘要： With the hope of overcoming the serious side effects, great endeavor has been made in tumor-targeted chemotherapy, and various drug delivery modalities and drug carriers have been made to decrease systemic toxicity caused by chemotherapeutic agents. Scientists from home and abroad focus on the research of targeted microbubbles contrast agent, and the use of the targeted ultrasound microbubble contrast agent can carry gene drugs and so on to the target tissue, as well as mediated tumor cell apoptosis and tumor microvascular thrombosis block, etc., thus plays the role of targeted therapy. Recent studies have elucidated the mechanisms of drug release and absorption, however, much work remains to be done in order to develop a successful and optimal system. In this review, we summarized the continuing efforts in understanding the usage of the ultrasound triggered target microbubbles in cancer therapy, from release mechanism to preparation methods. The latest applications of ultrasound-triggered targeted microbubbles in cancer therapy, especially in gene therapy and antiangiogenic cancer therapy were discussed. Moreover, we concluded that as a new technology, ultrasound–triggered targeted microbubbles used as drug carriers and imaging agents are still energetic and are very likely to be translated into clinic in the near future.

关键词： ultrasound-mediated     targeted microbubbles     cancer    

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Determining “abnormal” levator hiatus distensibility using three-dimensional transperineal ultrasound

Chaoran Dou, Qin Li, Tao Ying, Yulin Yan, Xia Wang, Bing Hu

《医学前沿（英文）》 2018年 第12卷 第5期   页码 572-579 doi: 10.1007/s11684-017-0561-4

摘要：

The dimension of the levator hiatus is a possible predictor of pelvic organ prolapse (POP). This retrospective study investigated 360 women who went to urogynecological clinic for pelvic floor discomfort. Levator hiatus dimensions were obtained by three-dimensional transperineal ultrasound and results were compared between women with and without significantly objective prolapse (International Continence Society POP quantification, grade 2 or higher). Receiver operating characteristic (ROC) curve analyses were performed to determine valid screening index for detecting abnormal levator hiatus distensibility. Women with significantly objective prolapse had significantly higher levator hiatus dimensions than those without (all P <0.001). ROC curve analyses confirmed that hiatal area (HA) of 19.5 cm2 during Valsalva maneuver can be used as single-screening index for abnormal levator hiatus distensibility with sensitivity of 0.80 and specificity of 0.70. In this study, we used a two-step method and achieved higher sensibility (0.80 vs. 0.87) without reducing specificity (0.70 vs. 0.71) compared with a single-screening index method. As a result, we suggest that HA≥19.5 cm2 during Valsalva maneuver is an indicator of abnormal levator hiatus distensibility in Chinese women and that the two-step method has higher sensitivity in detecting abnormal distensibility.

关键词： three-dimensional transperineal ultrasound     levator hiatus     levator ani muscle     pelvic organ prolapse    

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Study of ultrasound-promoted, lipase-catalyzed synthesis of fructose ester

Kai ZHU, Hui LIU, Pingfang HAN, Ping WEI,

《化学科学与工程前沿（英文）》 2010年 第4卷 第3期   页码 367-371 doi: 10.1007/s11705-009-0312-4

摘要： The effect of low energy ultrasound in biochemistry and biotechnology has attracted great attention in recent years. It can enhance substrate dissolution and improve mass transfer within and outside of a cell, both of which are beneficial to the synthesis of fructose ester. Here we describe the experimental study of the effect of ultrasounds of different intensity on the lipase-catalyzed synthesis of fructose ester in the solvent butanone. The results were compared with control reactions performed with no ultrasound. High performance liquid chromatography (HPLC) and thin layer chromatography (TLC) were used for qualitative and quantitative analyses. The results show the following: 1) the concentration of mono-ester and diester increased with the reaction time, either with or without ultrasonic irradiation. Low energy ultrasound accelerated the reaction due to the effect of ultrasonic steady cavitations, and high energy ultrasound was not beneficial to the reaction. 2) The application of ultrasound played an important role in our lipase-catalyzed reaction. It decreased reaction time as compared to a reaction without ultrasound that resulted in the same yield, increased reaction rate, and enhanced the amount of fructose ester produced. When the frequency was 10 kHz and sound intensity was 0.16 W·m, the concentration of ester was twofold more than without ultrasonic irradiation after a reaction time of up to 12 h. With the proper ultrasonic parameters, the overall concentration of production appeared to increase exponentially with the reaction time. 3) Ultrasound had little effect on the initial reaction rate, and continuous ultrasonic irradiation was favorable for the reaction. The longer the reaction continued, the more obvious the effects of the ultrasound became in our experiments.
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Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 298-306 doi: 10.1007/s11705-022-2212-9

摘要： Herein, a reversible pH fluorescent sensor was developed using caffeic acid as the precursor by one-step solvothermal synthesis method. The carbon dots-based sensor (CA-CDs) exhibited pH-dependent increase in fluorescence intensity and showed linear relationship in the range of pH 6.60 and 8.00. Notably, the fluorescence sensor has a reversible response to pH change. Finally, the CA-CDs has been successfully applied for two-photon imaging of the pH in liver and kidney of diabetic mice. Imaging results showed that the pH value in kidney of diabetic mice was lower than that of the normal mice, while the pH value in liver of diabetic mice was almost the same as that of the normal mice. The present study provides a simple analytical method for pH detection suitable for in vivo.

关键词： carbon dots     two-photon imaging     pH     diabetic mice    

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The value of ultrasound elastography in differential diagnosis of superficial lymph nodes

Yanrong ZHANG phD , Qing LV MD , Mingxing XIE MD , Feixiang XIANG phD , Chengfa LU BM , Tianwei YAN BM , Wei LI BM , Hui XU BM , Yan HUANG BM , Yehua YIN BM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 368-374 doi: 10.1007/s11684-009-0063-0

摘要： The study evaluated the value of ultrasound elastography in differentiating the benign and malignant superficial lymph nodes. A total of 112 subjects, including 82 patients with enlarged lymph nodes and 30 healthy volunteers, were recruited. All the subjects were examined by B-mode ultrasonography, power Doppler ultrasonography and elastography. Most of the patients were histopathologically confirmed by needle aspiration cytology and some patients were diagnosed by clinical data combined with follow-up findings. The sensitivity, specificity and accuracy of B-mode ultrasonography were 59.8%, 76.5% and 67.1%, those of the blood flow classification by power Doppler ultrasonography 77.0%, 82.3% and 79.4% and those of elastographic classification 74.7%, 97.1% and 84.5%, respectively. The elasticity of the lymph nodes was quantitatively measured and defined as stiffness value. When the stiffness value of 2.395 was taken as the cutoff point, the sensitivity and specificity of elastography were 78.41% and 98.51%, and the Youden index reached the highest, with the value being 0.7692. The stiffness values of two indeterminate benign lymph nodes, the elastrographic findings of which were rated as patterns 2 and 3, were below the cutoff point. The elastographic findings of 10 malignant lymph nodes were also classified as pattern 2 or 3. Only one of them had the stiffness values below the cutoff point. It was concluded that ultrasound elastography is a novel, noninvasive and convenient tool for the differentiation of the nature of the superficial lymph nodes in clinical practice.

关键词： ultrasound elastography     lymph node     power Doppler sonography    

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标题 作者 时间 类型 操作

Anefficient quadrature demodulator for medical ultrasound imaging

Hao ZHOU,Yin-fei ZHENG

期刊论文

High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

期刊论文

超声检查对胎儿畸形的诊断分析

李华洁

期刊论文

naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomal cellular imaging

Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

期刊论文

Ultrasonic linear motor using the L-B mode Langevin transducer with an exponential horn

SHI Shengjun, CHEN Weishan, LIU Junkao, ZHAO Xuetao

期刊论文

土石坝SH 波地震反射成像

Edward W. Woolery

期刊论文

Synthesis and characterization of phosphotungstic acid/activated carbon as a novel ultrasound oxidative

Liyan LIU, Yu ZHANG, Wei TAN

期刊论文

Studies of ultrasound disintegration of residual sludge and its energy consumption in water treatment

SHEN Jinfeng, YIN Xuan, GU Heping, Lv Xiaoping

期刊论文

evaluation of renal function using diffusion weighted imaging and diffusion tensor imaging in type 2

null

期刊论文

Using ultrasound to improve the sequential post-synthesis modification method for making mesoporous Y

Rongxin Zhang, Peinan Zhong, Hamidreza Arandiyan, Yanan Guan, Jinmin Liu, Na Wang, Yilai Jiao, Xiaolei Fan

期刊论文

Ultrasound-mediated targeted microbubbles: a new vehicle for cancer therapy

Junxiao YE, Huining HE, Junbo GONG, Weibing DONG, Yongzhuo HUANG, Jianxin WANG, Guanyi CHEN, Victor C YANG

期刊论文

Determining “abnormal” levator hiatus distensibility using three-dimensional transperineal ultrasound

Chaoran Dou, Qin Li, Tao Ying, Yulin Yan, Xia Wang, Bing Hu

期刊论文

Study of ultrasound-promoted, lipase-catalyzed synthesis of fructose ester

Kai ZHU, Hui LIU, Pingfang HAN, Ping WEI,

期刊论文

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

期刊论文

The value of ultrasound elastography in differential diagnosis of superficial lymph nodes

Yanrong ZHANG phD , Qing LV MD , Mingxing XIE MD , Feixiang XIANG phD , Chengfa LU BM , Tianwei YAN BM , Wei LI BM , Hui XU BM , Yan HUANG BM , Yehua YIN BM ,

期刊论文