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Ensuring high slope stability has become a critical technical challenge that threatens construction safety, restricts project progress, and affects safe operation. This research utilizes 3DEC software to establish the slope model, analyze the stability of high slopes with down-layer and anti-dip slab-cracked rock bodies using the discrete element method and strength reduction method, and investigate the influence of each feature of the slab-cracked rock body on the stability of the slab-cracked structure slope. Then, a slope was designed with the reinforcement scheme of “anchor anti-slip pile + prestressed anchor cable + drainage + slope protection” as an example to analyze the effectiveness of slope reinforcement under different anti-slip pile positions and sizes and to verify the effectiveness of the slope reinforcement scheme through the displacement changes of the slope. The results show that the slope safety coefficient is positively correlated with the rock mass, thickness, and strength of the cracked body. The most obvious effect is the rock mass, and the safety coefficients of the two kinds of cracked slopes when the rock mass is the highest are 4.464 and 6.714, respectively. The displacements in the X direction and the Z direction are reduced by 78.04% and 60.34%, respectively, and the reinforced design has played the role of limiting the decline of slopes. To some extent, it can ensure the effectiveness of the slope-reinforced scheme. The design of reinforcement plays an effective role in limiting slope decline, which can provide the stability of the slope to a certain extent.

ObjectiveTo analyze the morbidity and mortality characteristics and prevalence trends of asopharyngeal carcinoma among registered residents in Yuyao City of Zhejiang Province from 2012 to 2021， and to provide suggestions for the prevention and treatment of the cancer.MethodsThe incidence and mortality data of asopharyngeal carcinoma in Yuyao City from 2012 to 2021 were collected. The incidence， mortality， standardized rate， cut-off rate， cumulative rate and annual percentage of trend change were calculated. A linear logarithmic model was used to analyze the variation trend.ResultsFrom 2012 to 2021， the crude incidence rate was 6.46/105 in Yuyao， while the Chinese standard rate was 4.78/105 and the world standard rate was 3.68/105， which all increased over the years. The indicators in males were higher than these in females （χ2=85.377， P

Objective: To analyze detection rate and changing trend of clinical multi-drug resistant bacteria(MDRB) in recent 5 years, and explore drug resistance characteristics of carbapenem resistant gram-negative bacteria, so as to provide reference for nosocomial infection prevention and control and empirical treatment of antibiotics in clinical practice. Methods: Seven kinds of MDRB isolated from clinical specimens of hospitalized patients during January 2017 to December 2021 were retrospectively analyzed, including methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus (VRE), extended spectrum β-lactamases producing Escherichia coli (ESBL-eco), extended spectrum β-lactamases producing Klebsiella pneumoniae (ESBL-kpn), carbapenem resistant Enterobacteriaceae (CRE), carbapenem resistant Acinetobacter baumannii (CR-AB) and carbapenem resistant Pseudomonas aeruginosa (CR-PA). The rate of carbapenem resistant gram-negative bacilli to common antibiotics and the carbapenemase production of CRE strain were analyzed with SPSS 20.0. Results: VRE was not detected in this study. Except ESBL-eco, the isolated rates of the other five MDRB increased in the past five years. The detection rates of MRSA, ESBL-kpn, CRE, CR-AB and CR-PA fluctuated between 37.0%-53.6%, 19.3%-34.3%, 2.5%-10.6%, 34.1%-63.4% and 11.3%-22.8%, respectively. It revealed that 65.4% CRE, 72.0% CR-AB, and 59.3% CR-PA isolates were isolated from ICU. The resistant rates of CRE and CR-AB to quinolones, cephalosporins and β-Lactamase inhibitor complex were 90.0%. Among 272 CRE strains, 221 strains were Klebsiella pneumoniae, accounting for 81.3%. The carbapenemase was detected in 90 strains of CRE, in which three kinds of carbapenemases (KPC, NDM and IMP) were detected and the constituent ratio of KPC enzyme was 90.0%. Conclusions: The isolated rates of six MDRB in this study are much lower than the average level in Shanghai and national tertiary hospitals in the same period, but the isolated rates of MRSA, ESBL-kpn, CRE, CR-AB and CR-PA show an upward trend, which should be paid attention to, especially the carbapenem resistant gram-negative bacteria in ICU. In this study, 90 strains of CRE tested produced three kinds of carbapenem enzymes, in which KPC enzymes showed a high proportion.

Klebsiella pneumoniae is a pathogen that commonly causes hospital‐acquired infections. Bacterial biofilms are structured bacterial communities that adhere to the surface of objects or biological tissues. In this study, we investigated the genome homology and biofilm formation capacity of ESBL‐producing K. pneumoniae. Thirty ESBL‐producing K. pneumoniae isolates from 25 inpatients at Ruijin Hospital, Shanghai, were subjected to pulsed‐field gel electrophoresis (PFGE) to estimate genomic relatedness. Based on the chromosomal DNA patterns we obtained, we identified 21 PFGE profiles from the 30 isolates, eight of which had high homology indicating that they may have genetic relationships and/or potential clonal advantages within the hospital. Approximately 84% (21/25) of the clinical patients had a history of surgery, urinary tract catheterization, and/or arteriovenous intubation, all of which may have increased the risk for nosocomial infections. Biofilms were observed in 73% (22/30) of the isolates and that strains did not express type 3 fimbriae did not have biofilm formation capacity. Above findings indicated that a high percentage of ESBL‐producing K. pneumoniae isolates formed biofilms in vitro and even though two strains with cut‐off of PFGE reached 100% similarity, they generated biofilms differently. Besides, the variability in biofilm formation ability may be correlated with the expression of type 3 fimbriae. Thus, we next screened four ESBL‐producing K. pneumoniae isolates (Kpn5, Kpn7, Kpn11, and Kpn16) with high homology and significant differences in biofilm formation using PFGE molecular typing, colony morphology, and crystal violet tests. Kpn7 and Kpn16 had stronger biofilm formation abilities compared with Kpn5 and Kpn11. The ability of above four ESBL‐producing K. pneumoniae isolates to agglutinate in a mannose‐resistant manner or in a mannose‐sensitive manner, as well as RNA sequencing‐based transcriptome results, showed that type 3 fimbriae play a significant role in biofilm formation. In contrast, type 1 fimbriae were downregulated during biofilm formation. Further research is needed to fully understand the regulatory mechanisms which underlie these processes. [ABSTRACT FROM AUTHOR]