Browsing by Author "Wang, Cheng"

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    Developing the Use of UAV Imagery Systems for Site Specific Weed Management
    (2020-09-02) Hassanein, Mohamed; El-Sheimy, Naser; Lari, Zahra; Noureldin, Aboelmagd; Sousa, Mario; Wang, Cheng; Wang, Ruisheng
    The use of Unmanned Aerial Vehicle (UAV) imagery systems for Precision Agriculture (PA) applications drew a lot of attention through the last decade. UAV as a platform for an imagery sensor is providing a major advantage as it can provide high spatial resolution images compared to satellite platform. Also, it provides the user with the ability to collect the needed images at any time along with the ability to cover the agriculture fields faster than terrestrial platform. Therefore, these UAV imagery systems are capable to fit the gap between aerial and terrestrial Remote Sensing systems. Weed management is one of the important PA applications that using UAV imagery system for it showed great potentials. The current weed management procedure depends on spraying the whole agriculture field with chemical herbicides to execute any weed plants in the field. Although such procedure seems to be effective, it has huge effect on the surrounding environment due to the excessive use of the chemical, especially that weed plants don’t cover the whole field. Usually weed plants spread through only few spots of the field. Therefore, different efforts were introduced to develop weed detection techniques using UAV imagery systems. Though the different advantages of UAV imagery systems, such systems didn’t draw the users interest due to many limitations such as the cost of these systems. The primary objective of the research work is to develop the use of UAV imagery systems for PA with focus on weed management through tackling the different limitations of using UAV imagery systems for weed management. Therefore, different methodologies are introduced for vegetation segmentation, crop row detection, and weed detection. These methodologies are able to enhance the use of low-cost UAV imagery systems through targeting two main goals. First, the use of RGB imagery sensors. Second, collect the imagery data from high altitudes.
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    ERG Protein Expression Is of Limited Prognostic Value in Men with Localized Prostate Cancer
    (2013-08-19) Teng, Liang Hong; Wang, Cheng; Dolph, Michael; Donnelly, Bryan; Bismar, Tarek A.
    Background. The prognostic significance of ERG expression in prostate cancer (PCA) has generated mixed results. We sought to investigate the prognostic significance of ERG expression in a localized cohort of men with PCA. Material and Methods. We investigated ERG protein expression in a cohort of 198 men with localized PCA. ERG expression was correlated with patients' clinical outcome and several pathological parameters, including Gleason score (GS), pathological stage, surgical margin, and extra-capsular extension. Results. ERG expression was detected in 86/198 (43.4%) patients exclusively in neoplastic epithelium. Overall, ERG mean expression intensity was versus in acinar PCA compared to foamy type PCA (). In HGPIN, ERG intensity levels were comparable to those in foamy type PCA () but significantly lower than those in acinar PCA (). ERG expression was significantly associated with extra-prostatic extension and higher pathological stage and showed a trend toward seminal vesicle invasion. Herein, ERG expression was documented in 50/131 (38.1%) patients with pT2 versus 30/55 (54.5%) patients with pT3 (). ERG association with higher pathological stage was more pronounced in patients with . Grouping patients into those with versus 7, there was no significant association between ERG expression and GS. Similarly, no association was present in relation to either surgical margins or postsurgical serum PSA levels. Conclusion. We report significant association between ERG protein levels and extra-prostatic extension and higher pathological stage. ERG expression is not associated with adverse clinical outcome and is of limited prognostic value in localized PCA.