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The global proliferation of natural predators, including Terpios hoshinota sponge and crown-of-thorns starfish, poses a significant threat to the ecological vitality of coral reefs. However, coral reef research currently lacks comprehensive quantitative studies on the ramifications of predator outbreaks in various coral reef landform types. To bridge this knowledge gap, this study utilized a dataset comprising 26 Sentinel-2 remote sensing images spanning the years 2016 to 2022, both pre- and post-two distinct episodes of natural predator outbreaks involving the Terpios hoshinota sponge and crown-of-thorns starfish, within the vicinity of Taiping Island. High-resolution GF-2 (PMS) remote-sensing images and satellite data were used to augment the analysis. Based on data obtained from the Google Earth platform of the Geographic Information System for remote sensing imagery, we conducted an experiment involving the classification of coral reef landform types in Taiping Island in the South China Sea. During the Support Vector Machine (SVM) classification experiments, we performed a meticulous examination of the image interpretation outcomes, making comparisons and rectifications in consultation with domain experts. Classification was performed by analyzing remote sensing images, and the identified landform types included areas characterized by dense coral sedimentation, sparse coral sedimentation, coral clusters, sand flats, and shallow reef front slopes. Subsequent analyses focused on discerning distinctive characteristics and tracing their evolutionary patterns. The findings reveal that (1) this study effectively integrates expert interpretation knowledge and an SVM classification algorithm to classify the various landform types present in Taiping Island's coral reef ecosystem. Remarkably, the classification achieved an unprecedented level of accuracy, with an overall accuracy rate of 96.46% and a kappa coefficient of 0.94. (2) The analysis showed that during the two natural predator outbreaks, the coral reef landforms on Taiping Island, which included dense coral reef areas, dense coral sedimentation areas, and sparse coral sedimentation areas, displayed significant decreases in their respective areas. The outbreak of Terpios hoshinota sponge had the most profound impact on the dense coral sedimentation area, resulting in a 72.92% decrease in the total area. Meanwhile, the outbreak of crown-of-thorns starfish had the most significant effect on the coral cluster area, causing a 59.17% reduction in total area. (3) Over the period spanning from 2016 to 2022, the degradation rate of the coral reefs on Taiping Island exceeded the recovery rate. Notably, the highest degradation rate (23.88%) occurred between March-June 2017. Conversely, the highest rate of recovery (18.03%) was observed from June-September 2017. We analyzed the dynamic characteristics of coral reef landform types, including changes in type distribution, areal extent, degradation rate, and recovery rate. Furthermore, we assessed the influence of natural disturbances on the degradation of coral reef ecosystems, thereby providing valuable insights for conservation and scientific inquiries pertaining to coral reef ecological resources in the waters surrounding Taiping Island. This effort is underpinned by a solid theoretical foundation. The Chinese and English literature cited in this article have contributed significantly to various facets, including coral reef monitoring methodologies, construction of coral reef classification systems, and assessment of coral reef ecosystem health.

Background Remnant cholesterol (RC) is considered an important indicator to assess the risk of atherosclerotic cardiovascular disease (ASCVD), and the adverse effects of vulnerable plaque on the clinical prognosis of ASCVD patients has been demonstrated, however, there are few studies on the correlation between RC and vulnerable plaque characteristics.Objective To investigate the correlation between RC and vulnerable plaque characteristics in patients with acute coronary syndrome (ACS) .Methods One hundred and forth-two ACS patients admitted to Hebei general hospital who underwent percutaneous coronary intervention (PCI) and optical coherence tomography (OCT) from January 2017 to October 2021 were selected as the study subjects. The baseline data of the patients were collected, the characteristics of intracoronary plaques were analyzed by OCT, and the patients were divided into the TCFA group (25 cases) and the non-TCFA group (117 cases) according to the presence or absence of thin-cap fibroatheroma (TCFA) in OCT results. Multivariate Logistic regression was used to analyze the influencing factors of intracoronary TCFA in ACS patients. The receiver operating characteristic (ROC) curve was plotted to assess the predictive value of RC on TCFA; Spearman rank correlation was used to analyze the correlation between RC and intracoronary plaques characteristics.Results The proportion of patients with diabetes history and RC level in the TCFA group were higher than those in the non-TCFA group (P

Objective To study the resistance of Helicobacter pylori(Hp) isolated from Peking University People's Hospital to commonly used antibiotics, in order to provide basis for clinical rational drug use. Methods The drug susceptibility test data of Hp strains isolated from gastric mucosal biopsy specimens of outpatients in the Department of Gastroenterology, Peking University People's Hospital from May 2011 to December 2021 were retrospectively collected. The drug resistance rate and dual/multiple drug resistance of Hp to amoxicillin, metronidazole, clarithromycin, levofloxacin and tetracycline were statistically analyzed. Results A total of 120 Hp strains isolated from 402 gastric mucosa specimens (120 patients) and cultured positive were included, with a culture positive rate of 29.85%. The resistance rates of Hp to metronidazole (75.0%) and clarithromycin (72.5%) were relatively high, while the resistance rates to levofloxacin (45.8%), amoxicillin (12.5%) and tetracycline (4.2%) were relatively low. The drug resistance of Hp to clarithromycin and amoxicillin was not significantly affected by the age of the patients. The drug resistance rate to metronidazole and levofloxacin increased with the age of the patients, and the drug resistance rate to tetracycline decreased with the age of the patients. The resistance rate of female patients to levofloxacin was higher than that of male patients (56.7% vs. 32.1%, P=0.007). Over time, the resistance rate of Hp to clarithromycin increased gradually, the resistance rate to levofloxacin increased first and then decreased, the resistance rate to metronidazole fluctuated and was high overall, and the resistance rate to amoxicillin and tetracycline was not significantly affected by time and was relatively low overall. No Hp strains resistant to all five kinds of antibiotics were found. Dual drug resistance rate was 25.0%, with the simultaneous resistance of metronidazole and clarithromycin being the most common (20.0%); multiple drug resistance rate was 44.2%, with the simultaneous resistance of metronidazole + clarithromycin + levofloxacin being the most common (32.5%). Conclusions The resistance rate of Hp strains isolated from Peking University People's Hospital to metronidazole, clarithromycin and levofloxacin is high, and multiple drug resistance is serious. When carrying out empirical Hp root therapy in clinic, the drug regimen should be reasonably selected, and drug sensitivity test should be conducted when necessary, so as to guide the formulation of treatment regimen.