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Authors: Liu, Wen-Juan

Article Type: Research Article

Abstract: BACKGROUND: Strokes are the most common cause of death and the leading cause of acquired disability in adults worldwide. OBJECTIVE: The present study aimed to investigate the value of transcranial Doppler ultrasound (TCD) in the diagnosis of intracranial vascular stenosis in patients with a history of stroke. METHODS: This is a meta-analysis study of diagnostic tests. PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, Wanfang, and VIP databases were systematically searched. Diagnostic tests using TCD or transcranial colour Doppler ultrasound (TCCD) for detecting intracranial arterial stenosis in patients with a history of stroke were included, with reference standards of intracranial …angiography, computed tomography angiography (CTA), or magnetic resonance angiography. The risk bias map was drawn by Revman v5.3, the sensitivity and specificity forest plot was drawn by Stata v16.0, the receiver operating characteristic curve was drawn, and the area under the curve (AUC) was calculated. RESULTS: A total of 812 patients with stroke in 12 studies were included in the meta-analysis. The estimated sensitivity of TCD or TCCD for the detection of intracranial vascular stenosis was 0.77–1.00, and the combined sensitivity was 0.96 (95% confidence interval [CI]: 0.88–0.99); the estimated specificity was 0.32–1.00, and the combined specificity was 0.94 (95% CI: 0.82–0.98); the positive likelihood ratio was 15.8 (95% CI: 5.1–48.6); and the negative likelihood ratio was 0.04 (95% CI: 0.01–0.14). The AUC was 0.99 (95% CI: 0.97–0.99). CONCLUSION: Doppler ultrasound has good consistency with conventional methods for the diagnosis of intracranial artery stenosis in patients with a history of stroke. Different reference standards may affect sensitivity and specificity; when CTA was used as the reference standard, the consistency of the TCD in the diagnosis of intracranial artery stenosis in stroke patients was relatively good. Show more

Keywords: Transcranial Doppler, stroke, intracranial artery stenosis, diagnostic value

DOI: 10.3233/THC-220844

Citation: Technology and Health Care, vol. 32, no. 2, pp. 639-649, 2024

Authors: LIU, Wen-li | TANG, Bo

Article Type: Research Article

Abstract: Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetric method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml–1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitatively of carbaryl in cottonseeds.

Keywords: carbaryl, β-cycclodextrin, spectrofluorimetry, supramolecular interaction, determination

Citation: Journal of Environmental Sciences, vol. 16, no. 5, pp. 829-831, 2004

Authors: LIU, Wen-jun | ZHANG, Yong-ji

Article Type: Research Article

Abstract: The effects of UV intensity and turbidity on selected microbial indicator inactivation were investigated. Results showed that UV disinfection was effective in killing all the selected microbial indicators, the resistance order of the microorganisms was as follows: MS-2 coliphage > Bacillus subtilis > E. coli > Staphylococcus aureus and Candida albicans. UV intensity had influence on the inactivation of all the microorganisms, high UV disinfection efficency was obtained with higher UV intensity. Turbidity had impact on the bacteria inactivation rate, but there was no evidence that turbidity had any negative contribution to MS-2 coliphage. Under the same UV dosage, higher …UV intensity could overcome the negative influence of turbidity on UV performance, enhanced microorganism inactivation effect in turbidity water. Show more

Keywords: UV disinfection, intensity, exposure time, microbial indicator

Citation: Journal of Environmental Sciences, vol. 18, no. 4, pp. 650-653, 2006

Authors: Liu, Wen | Cheng, Yangjie | Liu, Dong C.

Article Type: Research Article

Abstract: Veterinary ultrasound has been used in a large number of animal husbandry-related circumstances while many corresponding applications also call for the use of ultrasound in human patients. However, veterinary ultrasound images are affected by speckle, an interference pattern that can reduce the quality and contrast of ultrasound images. In this paper, a filter-based receive-side spatial compounding technique for veterinary ultrasound B-Mode imaging is used to create a compounded veterinary B-Mode image based on multiple looks. In particular, filtering in the lateral direction has been proved to be able to preserve the axial information in the sub-bands and to create decorrelation …between sub-bands at the expense of some lateral resolution. A new method was proposed to obtain B-Mode IQ data by special veterinary ultrasonic probe. This approach is tested on 275 in-vivo swine. The effect is accomplished in real-time veterinary ultrasonic imaging with a measurable improvement of SNRe. Meanwhile, the speckle and electronic noise in the compounded image have been greatly reduced and smoothed in the visual result. Show more

Keywords: Speckle, spatial compounding, Veterinary ultrasound, filter-based

DOI: 10.3233/BME-130920

Citation: Bio-Medical Materials and Engineering, vol. 24, no. 1, pp. 1193-1199, 2014

Authors: Liu, Wen-Xin | Tang, Hong-xiao

Article Type: Research Article

Abstract: Based on numerous latest references, the current developments in surface complexation, surface precipitation and the corresponding models (SCMs and SPMs), were reviewed. The contents involved comparison on surface charge composition and layer-structure of solid-solution interface for the classical 1-pK and 2- pK models, In addition, the fundamental concept and relations of the new models, i.e., multi-site complexation (MUSIC) and charge -distribution (CD) MUSIC models were described as well. To avoid misuse or abuse, it must be emphasized that the applicability nd limitation for each model should be considered carefully when selecting the concerned model(s). In addition, some new powerful techniques …for surface characterization and analysis applied to model establishment and modification were also briefly introduced. Show more

Keywords: surface complexation models, geochemical circulation, environmental aquatic chemistry

Citation: Journal of Environmental Sciences, vol. 13, no. 4, pp. 422-434, 2001

Authors: Liu, Wen | Ma, Mingrui | Wang, Peng

Article Type: Research Article

Abstract: The widespread use of sensors has resulted in an unprecedented amount of time series data. Time series mining has experienced a particular surge of interest, among which, subsequence matching is one of the most primary problem that serves as a foundation for many time series data mining techniques, such as anomaly detection and classification. In literature there exist many works to study this problem. However, in many real applications, it is uneasy for users to accurately and clearly elaborate the query intuition with a single query sequence. Consequently, in this paper, we address this issue by allowing users to submit …a small query set, instead of a single query. The multiple queries can embody the query intuition better. In particular, we first propose a novel probability-based representation of the query set. A common segmentation is generated which can approximate the queries well, in which each segment is described by some features. For each feature, the corresponding values of multiple queries are represented as a Gaussian distribution. Then, based on the representation, we design a novel distance function to measure the similarity of one subsequence to the multiple queries. Also, we propose a breadth-first search strategy to find out similar subsequences. We have conducted extensive experiments on both synthetic and real datasets, and the results verify the superiority of our approach. Show more

Keywords: multiple queries, subsequence matching, time series mining, fault diagnosis

DOI: 10.15388/23-INFOR519

Citation: Informatica, vol. 34, no. 3, pp. 557-576, 2023

Authors: Liu, Wen Ming | Wang, Lingyu | Zhang, Lei | Zhu, Shunzhi

Article Type: Research Article

Abstract: Data owners are expected to disclose micro-data for research, analysis, and various other purposes. In disclosing micro-data with sensitive attributes, the goal is usually two fold. First, the data utility of disclosed data should be maximized for analysis purposes. Second, the private information contained in such data must be to an acceptable level. Typically, a disclosure algorithm evaluates potential generalization functions in a predetermined order, and then discloses the first generalization that satisfies the desired privacy property. Recent studies show that adversarial inferences using knowledge about such disclosure algorithms can usually render the algorithm unsafe. In this paper, we show …that an existing unsafe algorithm can be transformed into a large family of safe algorithms, namely, k -jump algorithms. We then prove that the data utility of different k -jump algorithms is generally incomparable. The comparison of data utility is independent of utility measures and syntactic privacy models. Finally, we analyze the computational complexity of k -jump algorithms, and confirm the necessity of safe algorithms even when a secret choice is made among algorithms. Show more

Keywords: Privacy preservation, micro-data disclosure, generalization

DOI: 10.3233/JCS-140514

Citation: Journal of Computer Security, vol. 23, no. 2, pp. 131-165, 2015

Authors: Hong, Yuan | Vaidya, Jaideep | Lu, Haibing | Liu, Wen Ming

Article Type: Research Article

Abstract: To make the search engine more user-friendly, commercial search engines commonly develop applications to provide suggestion or recommendation for every posed query. Clustering semantically similar queries acts as an essential prerequisite to function well in those applications. However, clustering queries effectively is quite challenging, since they are usually short, incomplete and ambiguous. Existing prevalent clustering methods, such as K-Means or DBSCAN cannot guarantee good performance in such a highly dimensional environment. Through analyzing users’ click-through query logs, hierarchical agglomerative clustering gives good results but is computationally quite expensive. This paper identifies a novel feature for clustering search queries based on …a key insight – queries’ top ranked search results can themselves be used to quantify query similarity. After investigating such feature, we propose a new similarity metric for comparing those diverse queries. This facilitates us to develop two very efficient and accurate algorithms integrated in query clustering. We conduct comprehensive experiments to compare the accuracy of our approach against the known baselines along two dimensions: 1) quantifying the cohesion/separation of clustered queries, and 2) justifying the results by real-world Internet users. The experimental results demonstrate that our two algorithms and the similarity metric can generate more accurate results within a significantly shorter time. Show more

Keywords: Web search, query log, clustering, top-k search results, clustering validation

DOI: 10.3233/WEB-160335

Citation: Web Intelligence, vol. 14, no. 2, pp. 119-138, 2016

Authors: Liu, Wen-xin | Coveney, R.M. | Tang, Hong-xiao

Article Type: Research Article

Abstract: FT-IR, Raman microscopy, XRD, {29}^Si and {27}^Al MAS NMR, were used to investigate changes in surface properties of a natural illite sample after acid-base potentiometric titration. The characteristic XRD lines indicated the presence of surface Al-Si complexes, preferable to Al(OH)_3 precipitates. In the microscopic Raman spectra, the vibration peaks of Si-O and Al-O bonds diminished as a result of treatment with acid, then increased after hydroxide back titration. The varied ratio of signal intensity between {IV}^Al and {VI}^At species in {27}^Al MAS NMR spectra, together with the stable BET surface area after acidimetric titration, suggested that edge faces and basal …planes in the layer structure of illite participated in dissolution of structural components. The combined spectroscopic evidence demonstrated that the reactions between illite surfaces and acid-leaching silicic acid and aluminum ions should be considered in the model description of surface acid-base properties of the aqueous illite. Show more

Keywords: natural illite, acid-base titration, spectroscopic information, surface Al-Si species, surface complexation

Citation: Journal of Environmental Sciences, vol. 15, no. 4, pp. 456-463, 2003

Authors: McIntire, Kevin | Asher, Marc | Burton, Douglas | Liu, Hongzeng | Liu, Wen

Article Type: Research Article

Abstract: A standardized protocol for assessing trunk rotational strength symmetry has not been established. Opposing muscle (agonist/antagonist) strength ratios have been used to assess strength asymmetry of appendicular joints but not the asymmetry of trunk rotational strength. The purpose of this study was to develop a protocol for measuring isometric trunk rotational strength with proper data analysis to assess rotational strength asymmetry. Methods: Maximum isometric trunk rotational strength of twenty healthy young adults, 12 women (25.1 ± 3 years), 8 men (30.1 ± 5.6 years), was measured at 5 positions of trunk rotation on two different days by two different testers. …Strength asymmetry was assessed in several ways including F-tests, percent-differences, and strength ratios. Results: Trunk strength was symmetrical at neutral and 18° testing positions. In the 36° pre-rotated trunk positions, right contractions toward neutral tended to be stronger than left contractions; whereas left contractions away from neutral tended to be stronger than right contractions. Conclusions: Our findings suggest caution when interpreting asymmetry at the 36° pre-rotated position. These methods of testing and assessing rotational strength asymmetry may be useful in patient populations in which strength asymmetry is hypothesized. Show more

Keywords: Trunk rotational strength, quantitative measurement, spinal muscles, reliability, strength ratios, strength asymmetry

DOI: 10.3233/IES-2007-0272

Citation: Isokinetics and Exercise Science, vol. 15, no. 3, pp. 183-194, 2007