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1.
Sensors (Basel) ; 24(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38732941

ABSTRACT

SAR imagery plays a crucial role in geological and environmental monitoring, particularly in highland mountainous regions. However, inherent geometric distortions in SAR images often undermine the precision of remote sensing analyses. Accurately identifying and classifying these distortions is key to analyzing their origins and enhancing the quality and accuracy of monitoring efforts. While the layover and shadow map (LSM) approach is commonly utilized to identify distortions, it falls short in classifying subtle ones. This study introduces a novel LSM ground-range slope (LG) method, tailored for the refined identification of minor distortions to augment the LSM approach. We implemented the LG method on Sentinel-1 SAR imagery from the tri-junction area where the Xiaojiang, Pudu, and Jinsha rivers converge at the Yunnan-Sichuan border. By comparing effective monitoring-point densities, we evaluated and validated traditional methods-LSM, R-Index, and P-NG-against the LG method. The LG method demonstrates superior performance in discriminating subtle distortions within complex terrains through its secondary classification process, which allows for precise and comprehensive recognition of geometric distortions. Furthermore, our research examines the impact of varying slope parameters during the classification process on the accuracy of distortion identification. This study addresses significant gaps in recognizing geometric distortions and lays a foundation for more precise SAR imagery analysis in complex geographic settings.

2.
Comput Math Methods Med ; 2022: 8211389, 2022.
Article in English | MEDLINE | ID: mdl-36213585

ABSTRACT

Objective: A case-control study was conducted to determine the effectiveness of laparoscopic surgery and traditional open surgery on stone clearance, laboratory indexes, and life quality in patients with renal calculi. Methods: During March 2017 to March 2022, 272 patients with complex renal calculi (CRC) cured in our hospital were assigned into control group (n = 136) and research group (n = 136) arbitrarily. The former accepted traditional open surgery, while the latter accepted laparoscopic surgery. The operation time, intraoperative blood loss, hospital stay, and time of getting out of bed were compared. The degree of postoperative incision pain was assessed by visual analogue scale (VAS). The life quality was assessed by the Comprehensive Assessment Questionnaire-74 (GQOL-74). The indexes of renal function and urine metabolism were measured. Then, the postoperative stone clearance rate and complications were calculated. Results: Operation time, blood loss intraoperatively, time out of bed, and hospitalization were all remarkably reduced in the research group, and the difference was statistically significant (P < 0.05). The complete stone clearance rates in study and control cohorts were 75.73% and 63.24%, respectively. The VAS scores were lessened after the operation. Compared with the two groups, the VAS scores of the research group were remarkably lower at 1 to 2 weeks and 1 and 3 months after the operation, and the difference was statistically significant (P < 0.05). One week after operation, the levels of ß 2-microglobulin (ß 2-MG), N-acetyl-ß-glucosaminidase (NAG), and renal injury molecule-1 (kidney injury molecule-1, Kim-1) in the research group were remarkably lower. The levels of urinary ß 2-MG, NAG, and KIM-1 in the research group were remarkably lower, and the difference was statistically significant (P < 0.05). One week after operation, the levels of urinary oxalic acid, uric acid, and urinary calcium lessened averagely. The levels of urinary oxalic acid, uric acid, and urinary calcium in the research group were lower, and the difference was statistically significant (P < 0.05). The quality-of-life scores were compared. One week after the operation, the scores of physical function, psychological function, social function, and material function were all augmented, and the difference was statistically significant (P < 0.05). The incidence of complications was 9.56% and 2.21%, respectively. The incidence of complications in the research group was lower, and the difference was statistically significant (P < 0.05). Conclusion: Laparoscopic surgery is successful when treating CRC, which is superior to invasive surgery in postoperative complications, stone clearance rate, improvement of postoperative renal function, and life quality. It is one of the ideal treatment methods for CRC. However, the role of open surgery when treating CRC cannot be ignored. This needs to be further confirmed by large samples of randomized controlled trials.


Subject(s)
Kidney Calculi , Laparoscopy , Calcium , Case-Control Studies , Hexosaminidases , Humans , Kidney Calculi/surgery , Laparoscopy/adverse effects , Oxalic Acid , Quality of Life , Retrospective Studies , Treatment Outcome , Uric Acid , beta 2-Microglobulin
3.
Comput Math Methods Med ; 2022: 2378113, 2022.
Article in English | MEDLINE | ID: mdl-35941896

ABSTRACT

Objective: A case-control study was conducted to compare the efficacy and prognostic factors of flexible ureteroscopic lithotripsy (FURL) and percutaneous nephrolithotomy (PCNL) when treating complex upper urinary tract renal calculi based on a retrospective cohort study. Methods: The study period was from October 2019 to December 2021. A retrospective study was carried out on 100 patients with complicated upper urinary tract nephrolithiasis who underwent surgery in the Urology Department of our hospital. They were assigned into two groups: FURL and PCNL groups. The intraoperative blood loss, operation time, hematuria duration, hospital stay, primary stone removal rate, incidence of intraoperative and postoperative complications, VAS score, level of inflammatory factors, and micturition function were compared. According to the postoperative prognosis, the patients were reassigned into two groups: good prognosis group (n = 38) and poor prognosis group (n = 106). The factors related to poor prognosis after FURL and PCNL were screened, and multivariate loglistic regression analysis was adopted to determine the risk factors. Results: The primary stone clearance rate in the PCNL group was significantly higher than that in the FURL group, and there was no significant difference in the incidence of intraoperative and postoperative complications between the two groups (P > 0.05). The intraoperative blood loss and the duration of hematuria in the PCNL group were significantly shorter than those in the FURL group, and the operation time and postoperative hospital stay in the FURL group were longer than those in the FURL group. The postoperative VAS score in the study group was significantly lower than that in the control group (P < 0.05). The levels of CRP, IL-1, TNF-α, and NF-κB in both groups decreased after operation, and the level of inflammatory factors in the PCNL group was significantly lower than that in the FURL group (P < 0.05). The indexes of IPSS and Q max in the PCNL group were significantly lower than those in the control group 3 months after operation. The index of micturition function in the PCNL group was significantly lower than that in the FURL group. Preoperative use of immunosuppressant, preoperative stone fever, positive preoperative urine culture, preoperative urinary leukocyte count ≥ 544 × L, intraoperative urinary opacity, and pus fur were significantly correlated with poor prognosis of ureteral patients (P < 0.05). Preoperative stone fever, high preoperative urinary leukocyte count, intraoperative urinary turbidity, and suppurative fur were independent risk factors for postoperative SIRS in patients with ureteral calculi. Conclusion: PCNL is effective when treating complex upper urinary tract renal calculi. Compared with FURL, PCNL can remarkably reduce intraoperative blood loss and hematuria duration, can enhance micturition function, and will not remarkably increase the incidence of intraoperative and postoperative complications, high safety. High white blood cell count in urine before operation, fever due to stone before operation, turbid urine, and purulent fur during operation are independent risk factors for postoperative adverse outcome in patients with complex upper urinary tract renal calculi. Patients should be fully treated before surgery.


Subject(s)
Kidney Calculi , Lithotripsy , Nephrolithotomy, Percutaneous , Ureter , Blood Loss, Surgical , Case-Control Studies , Hematuria/etiology , Hematuria/therapy , Humans , Kidney Calculi/etiology , Kidney Calculi/surgery , Lithotripsy/adverse effects , Nephrolithotomy, Percutaneous/adverse effects , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Retrospective Studies , Treatment Outcome , Ureteroscopy/adverse effects
4.
Sensors (Basel) ; 21(5)2021 Feb 28.
Article in English | MEDLINE | ID: mdl-33670835

ABSTRACT

At present, in the field of video-based human action recognition, deep neural networks are mainly divided into two branches: the 2D convolutional neural network (CNN) and 3D CNN. However, 2D CNN's temporal and spatial feature extraction processes are independent of each other, which means that it is easy to ignore the internal connection, affecting the performance of recognition. Although 3D CNN can extract the temporal and spatial features of the video sequence at the same time, the parameters of the 3D model increase exponentially, resulting in the model being difficult to train and transfer. To solve this problem, this article is based on 3D CNN combined with a residual structure and attention mechanism to improve the existing 3D CNN model, and we propose two types of human action recognition models (the Residual 3D Network (R3D) and Attention Residual 3D Network (AR3D)). Firstly, in this article, we propose a shallow feature extraction module and improve the ordinary 3D residual structure, which reduces the parameters and strengthens the extraction of temporal features. Secondly, we explore the application of the attention mechanism in human action recognition and design a 3D spatio-temporal attention mechanism module to strengthen the extraction of global features of human action. Finally, in order to make full use of the residual structure and attention mechanism, an Attention Residual 3D Network (AR3D) is proposed, and its two fusion strategies and corresponding model structure (AR3D_V1, AR3D_V2) are introduced in detail. Experiments show that the fused structure shows different degrees of performance improvement compared to a single structure.


Subject(s)
Human Activities , Neural Networks, Computer , Humans , Pattern Recognition, Automated , Video Recording
5.
ACS Omega ; 5(2): 995-1002, 2020 Jan 21.
Article in English | MEDLINE | ID: mdl-31984255

ABSTRACT

Combination therapy is emerging as a preferable approach in cancer therapy with minimized side effects and elevated performance. Nevertheless, the poor targeting and drug loading of currently available drug delivery systems (DDSs) are the main difficulties to realize preferable combination therapy of cancer. As a result, a cancer cell membrane-decorated zeolitic-imidazolate framework hybrid nanoparticle (HP) was successfully constructed in our study to codeliver cisplatin (DDP) and oleanolic acid (OLA). Our results showed positive results of the platform (HP/DDP/OLA) for the treatment of bladder cancer (SW780). In detail, HP/DDP/OLA could enhance apoptosis while reverse multidrug resistance in SW780 cells than free drugs alone or monodelivery systems, which might be a suitable DDS for codelivery of different drugs with great promise.

6.
Radiat Res ; 192(4): 422-430, 2019 08.
Article in English | MEDLINE | ID: mdl-31390309

ABSTRACT

Photodynamic therapy (PDT) uses a combination of photosensitizers with visible light to generate reactive species and selectively kill tumor or unwanted tissue. Znln2S4 nanoparticles are widely implemented in photovoltaic device materials and photolysis water catalysts owing to their unique photoelectric properties. Whether Znln2S4 itself can be used as an effective dye in PDT is still unknown. To determine the effects and potential mechanism of Znln2S4PDT on HepG2 cell apoptosis, electron microscopic analysis was performed to monitor the apoptotic morphology of HepG2 cells upon exposure to Znln2S4-PDT. Flow cytometry was performed to measure the apoptosis rate and intracellular ROS production. Western blot and ELISA were performed to reveal the expression changes in Bax, caspase-3 and caspase-9. Data from this work suggested that cells exhibited the typical apoptotic morphology in response to Znln2S4-PDT, with high apoptotic rate. The intracellular ROS production after Znln2S4-PDT occurred in a dose-dependent manner. Moreover, Znln2S4-PDT augmented the expression levels of pro-apoptosis factors, especially, Bax, caspase-3 and caspase-9. Taken together, our novel findings, Znln2S4-PDT elicited HepG2 cell apoptosis, suggesting Znln2S4 as a promising photosensitizer candidate for cancer therapy.


Subject(s)
Apoptosis/drug effects , Apoptosis/radiation effects , Indium/pharmacology , Photochemotherapy , Photosensitizing Agents/pharmacology , Zinc Compounds/pharmacology , Dose-Response Relationship, Drug , Hep G2 Cells , Humans , Intracellular Space/drug effects , Intracellular Space/metabolism , Intracellular Space/radiation effects , Membrane Potential, Mitochondrial/drug effects , Membrane Potential, Mitochondrial/radiation effects , Reactive Oxygen Species/metabolism
7.
Sci Total Environ ; 487: 154-63, 2014 Jul 15.
Article in English | MEDLINE | ID: mdl-24784740

ABSTRACT

In this paper, we first analyze the 5 most cited papers with the title containing "Urban ecosystem health" in Chinese academic journals, and 5 newer papers retrieved from the CSSCI (Chinese Social Sciences Citation Index). The results show that the number of indicators to be used together in more than three papers is 28, and then we select 27 of them to assess Beijing and Shanghai's urban ecosystem health from 2000 to 2011. Secondly, when we standardize the original data, the worst value adjustment coefficient is introduced innovatively. Thirdly, using the entropy method, the weights of concrete indicators of Beijing and Shanghai in the different adjustment coefficients are calculated respectively. Fourthly, based on the fuzzy matter-element method, using the Hamming approach degree, the two cities' ecosystem health index and the contribution value to overall health index from each component are calculated. Lastly, using gray prediction model, the evolutionary time response sequence function of Beijing and Shanghai's urban ecosystem health index is identified, and thus both cities' urban ecosystem health is predicted.


Subject(s)
Cities/statistics & numerical data , Ecosystem , Environmental Monitoring/methods , Urban Health/statistics & numerical data , China , Forecasting
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