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To get the best strategy of submarine underwater acoustic countermeasure against active/passive airborne sonar in normal conditions, this paper constructs the underwater acoustic environment model, sonar detection model and submarine underwater acoustic countermeasure model, proposes an airborne sonar information processing model considering acoustic contact, tracking, positioning and recognition processing, and simulates and analyzes the effectiveness of different submarine underwater acoustic countermeasure in the conditions of sonar contacting submarines. The results show that it is more effective to reduce the radiated noise than to increase the speed against the passive sonar. Submarines should adopt greater depth, minimum noise speed and shortest distance separation. If the submarine recognizes the position of the passive sonar buoy based on electronic reconnaissance or listening to the sound of sonobuoy impacting water, it can insert the bubble shell to worsen the common view condition of the passive buoy array, which avoids tracking and positioning and improves the effectiveness of countermeasures. It is the best strategy for the submarine to counter the active sonar, change the course, and release the wideband jammers and decoys at a high speed.The bubble shell can be released to worsen the sonar tracking, positioning and recognition environment while submarine fleeing, which providing conditions for the submarine to extend the distance from the sonar. The research in this paper can provide a simulation environment and decision-making reference for submarine underwater acoustic countermeasure active/passive airborne sonar.

Objective To identify the relationship between Rho guanine nucleotide exchange factor 7 (ARHGEF7) genetic variants and the formation and rupture risk of intracranial aneurysms. Methods Ten variants of the ARHGEF7 were detected in a case-control study which included 121 patients with intracranial aneurysms (including 41 unruptured and 80 ruptured patients) and 155 healthy controls. The relationship between variants and occurrence and rupture risk of intracranial aneurysms was examined by multivariate logistic regression model. Results After adjustment for age, sex, and traditional cardiovascular risk factors, the rs4145274GA genotype was associated with a decreased rupture risk of intracranial aneurysms as compared with rs4145274GG genotype, and odds ratio was 0.24[95% confidence interval (CI):0.09~0.69, P＜0.05]. The rs1555751CT genotype was also associated with a decreased rupture risk of intracranial aneurysms as compared with rs1555751CC genotype, and odds ratio was 0.17(95% CI: 0.05~0.63, P＜0.05). The combined effect rs4145274 and rs1555751 suggested that the patients with an increased genetic risk score had a lower rupture risk of intracranial aneurysms, and the odds ratio was 0.14(95% CI: 0.04~0.55, P＜0.05). Conclusions The study indicates that ARHGEF7 genetic variants potentially serve as potential genetic markers for the risk evaluation of ruptured intracranial aneurysms.

BackgroundThe 2020 Chinese guidelines for ultrasound malignancy risk stratification of thyroid nodules: the C-TIRADS (C-TIRADS for short) put forward a method for stratifying the malignancy risk of thyroid nodules, but there are few studies about its value in differentiating benign and malignant thyroid nodules.ObjectiveTo compare the value of ultrasound-based thyroid nodule malignancy risk stratification in differentiating malignant and benign thyroid nodule between C-TIRADS and 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: the American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer (ATA guidelines for short) .MethodsA total of 336 inpatients who underwent surgery and ultrasound examination in Bozhou People's Hospital from January 2019 to May 2021 were selected as participants. Four ultrasonologists with a title higher than attending physician were equally randomized into groups A and B for evaluating ultrasonic examination results according to ultrasound-based thyroid nodule malignancy risk stratification in C-TIRADS and ATA guidelines, respectively. The accuracies of ultrasound-based thyroid nodule malignancy stratification in the two guidelines in differentiating malignant and benign thyroid nodules were assessed using intraoperative or postoperative pathological findings (gold standard for diagnosis) , and were further analyzed using ROC analysis.ResultsAccording to intraoperative or postoperative pathological findings, the participants had 367 thyroid nodules in total, including 253 benign nodules and 114 malignant nodules. The nodules were classified as follows according to the TI-RADS in the C-TIRADS by ultrasonologists in group A: (1) 253 benign nodules: 2 were in TI-RADS 5 category, 23, 30, and 80 were in categories 4c, 4b, and 4a, respectively, 103 were in 3 category, and 15 were in 2 category; (2) 114 malignant nodules: 24 were in TI-RADS 5 category, 59 were in 4c category, 22 were in 4b category, 6 were in 4a category and 3 were in 3 category. And the classification of nodules according to the ATA guideline by ultrasonologists in group B was: (1) 253 benign nodules: 13, 53, 47, 118 were high, intermediate, low, and very low suspicion pattern for malignancy, respectively, and 22 were benign pattern; (2) 114 malignant nodules: 76, 24, 8, 6 were high, intermediate, low, and very low suspicion pattern for malignancy, respectively. ROC analysis showed that, AUCs of ultrasound-based thyroid nodule malignancy risk stratification in differentiating malignant and benign thyroid nodules between C-TIRADS and ATA guidelines were 0.890〔95%CI (0.815, 0.918) 〕and 0.780〔95%CI (0.750, 0.876) 〕, with significant difference (Z=13.62, P

Objective: To determine the risk factors of delirium in elderly patients after hip fracture surgery. Methods: We searched electronic bibliographic databases for eligible original studies published until November 2022. After literature screening, data extraction and quality evaluation, meta-analysis was performed using Stata17.0 and RevMan5.4. Results: A total of 16 studies were included, The incidence of delirium in elderly patients with hip fracture was 23.0% [95%CI= (20%~26%)]. The main risk factors for perioperative delirium in elderly patients with hip fracture were advanced age [OR=1.24, 95%CI = (1.10-1.40), P< 0.001], pain [OR=2.01, 95% CI = (1.48-2.75), P<0.001], stroke history [OR=5.22, 95%CI = (2.75-9.92), P<0.001], complications ≥3 [OR = 2.25,95%CI = (1.33-3.81), P=0.002], preoperative cognitive dysfunction [OR=3.45, 95%CI = (2.51-4.75), P<0.001], hypoxemia [OR=3.91, 95%CI = (2.70-5.67), P<0.001], long preoperative wait time [OR=3.98, 95%CI = (1.16-13.98), P=0.030], general anesthesia [OR=2.55, 95%CI = (1.81-3.59), P<0.001], long operation time [OR=1.61, 95%CI = (1.22-2.11), P<0.001], preoperative low albumin [OR=6.42, 95% CI= (2.59-15.88), P<0.001], low BMl [OR= 3.06, 95% CI= (1.71-5.46), P<0.001]. Conclusion: The incidence of postoperation delirium in elderly patients of hip fracture is high and there are many influencing factors. Early screening and intervention for delirium risk should be carried out to reduce the impact of adverse outcomes on patients. [ABSTRACT FROM AUTHOR]

The effects of the proportions of epoxy emulsion and antirust agent on the main properties of waterborne anticorrosive paint were studied. The results showed that the epoxy emulsion prepared with 14% (mass fraction) of DER- 425 epoxy modified emulsifier and 56% (mass fraction) of DER-439 epoxy resin had an average particle size of 923 nm, a viscosity of 4.1 Pa·s, and good resistance to sulfuric acid, hydrochloric acid, acetone, and dichloroethane. The epoxy emulsion was modified with 0.6% (mass fraction) of graphene, and then used to prepare a paint by blending it with a zinc aluminum phosphite antirust agent at a mass ratio of (6-8):1. The cured coating of the paint can endure neutral salt spray corrosion for 1 104 hours, 1 kg impact from a height of 50 cm, immersion in acids, and being rubbed by organic media. [ABSTRACT FROM AUTHOR]

Utilizing the data of 328 cities in China from 2003 to 2019, this paper adopts the vertical and horizontal scatter-grade method, fixed base efficacy method, and social network analysis method to estimate the level of high quality development of these cities, and further analyzes the characteristics, transmission mechanism and influencing factors of the spatial correlation network for high quality development. It is found as follows. ➀ The average value of high quality development indexes of cities in China is on the rise and the high quality development level from high to low is the eastern, central, western and northeastern regions, and the number of medium-level and medium-high-level cities is increasing year by year. ➁ The spatial correlation network density of high quality development is high, and the majority of cities with high centrality are distributed in the central region. The spatial correlation network can be divided into eight sectors, comprising three bidirectional spillover sectors, one net spillover sector, two broker sectors, and two main beneficiary sectors. The spillover sectors are concentrated in the eastern coastal and central regions, while the beneficiary sectors are mostly located in the western region. There are multiple transmission paths between the sectors, and the broker sector plays a bridge role in it. ➂ The formation of spatial correlation network of high quality development is mainly attributed to the differences in economic development, governmental intervention, and geographical proximity among cities. [ABSTRACT FROM AUTHOR]

Octadecane/expanded graphite and paraffin/expanded graphite shape-set phase change material precursors were prepared by vacuum adsorption. The medium and low-temperature dual-stage phase change polyu-rethane rigid foam was prepared by a one-step foa ming method. Cell structure, mechanical properties, phase change properties, thermal stability and temperature regulation capability of polyurethane rigid foams were investigated by SEM, DSC, TGA, universal testing machine and other test methods. The results showed that when the dual-stage phase change material was 95 wt%, the melting enthalpy and crystallization enthalpy of the medium-low temperature dual-stage phase-change polyurethane rigid foam reached 58.29 J/g and 53.69 J/g, respectively. Tow constant temperature platforms appeared at 26 °C and 60 °C, respectively in the process of uniform heating and cooling, showing excellent temperature regulation and control ability. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the relationship between the virulence and the carbapenem resistance phenotype of Klebsiella pneumoniae from blood infection, and to identify carbapenem-resistant and hypervirulent Klebsiella pneumoniae (CR-HVKP)strains., Methods: A total of 192 Klebsiella pneumoniae strains were isolated from blood culture of patients with bloodstream infections from 2016 to 2019, of which 96 isolates were carbapenem-resistant Klebsiella pneumoniae (CRKP) and 96 were carbapenem-sensitive Klebsiella pneumoniae (CSKP). The drug susceptibility was detected by VITEK-2 automatic microbial analyzer; carbapenemase genes, virulence genes and capsule typing were detected by polymerase chain reaction; the high viscosity phenotype of strains was detected by string test, and the genome characteristics of CR-HVKP were detected by whole genome sequencing. Serum killing and biofilm formation test were used to further verify the virulence of CR-HVKP., Results: There were significant differences in drug resistance to common antibiotics, except for minocycline between CSKP and CRKP isolates (all P <0.05). 92 out of 96 CRKP isolates carried carbapenemase genes, mainly bla KPC - 2 . The string tests were positive in 4 isolates of CRKP and 36 isolates of CSKP ( P <0.05). The detection rates of virulence genes Kfu , aerobictin , iutA , ybtS , rmpA , magA , allS , and capsule antigen K1 and K2 in CSKP group were significantly higher than those in CRKP group (all P <0.05). One HVKP strain was detected in the CRKP group (CR-HVKP) and 36 HVKP was detected in the CSKP group ( P <0.05). The CR-HVKP strain belonged to the MLST412, serotype K57, expressed iutA , entB , mrkD , fimH , and rmpA virulence genes, and showed strong biofilm formation and significantly increased serum resistance. Whole genome sequencing results showed that this CR-HVKP isolate carried bla SHV - 145 , bla TEM - 1 , bla CTX - M - 3 , fosA6 , oqxA5 , oqxB26 , and aac(3) - IId resistance genes, accompanied by abnormalities in outer membrane protein K (OmpK) 35 and OmpK36., Conclusions: The drug resistance of CRKP is significantly higher than that of CSKP, while CRKP carrying fewer virulence genes in both number and types compared to CSKP. A new MLST type of carbapenem-resistant and hypervirulent Klebsiella pneumoniae strain has been detected, which requires clinical awareness and epidemiological monitoring.

Objective: To investigate the clinical characteristics and molecular epidemiology of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolated from patients with bloodstream infections in a large tertiary-care general hospital in Southwest China., Methods: A total of 131 strains of non-repeating CRKP were collected from the blood cultures of patients who had bloodstream infections in 2015-2019. The strains were identified by VITEK-2, a fully automated microbial analyzer, and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. The minimum inhibitory concentration (MIC) was determined by microbroth dilution method. The common carbapenemase resistant genes and virulence factors were identified by PCR. Homology analysis was performed by multilocus sequencing typing. Whole genome sequencing was performed to analyze the genomic characteristics of CRKP without carbapenemase., Results: The 131 strains of CRKP showed resistance to common antibiotics, except for polymyxin B (1.6% resistance rate) and tigacycline (8.0% resistance rate). A total of 105 (80.2%) CRKP strains carried the Klebsiella pneumoniae carbapenemase ( KPC ) resistance gene, 15 (11.4%) strains carried the New Delhi Metallo-β-lactamase ( NDM ) gene, and 4 (3.1%) isolates carried both KPC and NDM genes. Sequence typing (ST) 11 (74.0%) was the dominant sequence type. High detection rates for mrkD (96.2%), fimH (98.5%), entB (100%), and other virulence genes were reported. One hypervirulent CRKP strain was detected. The seven strains of CRKP that did not produce carbapenemase were shown to carry ESBL or AmpC genes and had anomalies in membrane porins OMPK35 and OMPK36, according to whole genome sequencing., Conclusion: In a large-scale tertiary-care general hospital, CRKP mainly carries the KPC gene, has a high drug resistance rate to a variety of antibiotics, and possesses multiple virulence genes. Attention should be paid to CRKP strains with high virulence., Competing Interests: 利益冲突　所有作者均声明不存在利益冲突, (© 2024《四川大学学报（医学版）》编辑部 版权所有Copyright ©2024 Editorial Board of Journal of Sichuan University (Medical Sciences).)

Objective To investigate the effect of miR-328-3p on the invasion and migration of colorectal cancer cells induced by interleukin-17 (IL-17) and its mechanism. Methods Real-time quantitative PCR was used to detect the expressions of miR-328-3p, FOXP3, and IL-17 mRNA in FHC colorectal epithelial cells and colorectal cancer cells (HCT116, Caco-2, and LoVo). Transwell TM assay was used to detect cell invasion and migration, and gelatin zymography assay to detect the activities of matrix metalloproteinases 2 (MMP2) and MMP9. Dual luciferase reporter assay was conducted to detect the targeted regulation relationship between miR-328-3p and FOXP3. The level of FOXP3 protein in Caco-2 cells was detected by Western blot analysis. Results Compared with those in colorectal epithelial cells, the expression level of miR-328-3p in colorectal cancer cells decreased, while the levels of FOXP3 and IL-17 increased. Transfection of miR-328-3p mimics inhibited the invasion and migration ability of IL-17-induced Caco-2 cells and the activities of MMP2 and MMP9 in the cells. miR-328-3p directly targeted and inhibited the protein level of FOXP3 in Caco-2 cells. Overexpression of FOXP3 partly reversed the effect of miR-328-3p mimics on the invasion and migration ability of IL-17-induced Caco-2 cells and the activities of MMP2 and MMP9 in the cells. Conclusion miR-328-3p inhibits the invasion and migration of IL-17-induced Caco-2 cells by down-regulating FOXP3.

Transcription factor is a key trans-acting factor to mediate stress response by regulating gene expression. Plants have developed a series of mechanisms to modulate development, stress response, signaling and disease resistance at transcription level. DNA binding with one finger (DOF), containing one C₂-C₂ zinc finger domain, is a special plant transcription factor. Specifically, the conserved domain at N-terminus of DOF has multiple functions, including interacting with DNA and protein, which could be involved in plant development and stress response. Although many DOF family genes are characterized in plant stress response, it is not clear if DOF genes have functions in cereal plants. In the present paper, the role of DOF family genes on cereal plants were discussed based on a comprehensive phylogenetic relationship analysis, expression profiles in different tissues and various environmental conditions. The results obtained here will provide an important reference for further understanding the mechanism of gramineous crops in stress resistance.

In the process of hemodialysis, the patients' blood pressure and pulse wave are likely to change considerably so that hypotension and rapid heart rate may be dangerous to the hemodialysts' life. Based on the environment of hemodialysis room, we designed the communication system using SPCE061A single-chip computer and STC89C52 single-chip computer to realize wireless communication between upper system and the two single-chip computers, and on the upper computer the pulse wave can display at real-time and save data on the data base. At the same time we designed an interface program to reduce noise by way of frequency domain analysis and wavelet denoising. It can draw the cycle pulse wave, eigenvalue-K, the maximum peak and peak frequency, it can effectively judge a racing heart in the hemodialysis and can also evaluate vascular sclerosis of hemodialysis. In short, the system is able to improve treatment security and reduce the burden of the doctors and nurses in hemodialysis rooms.

Objective To investigate the efficiencies of transfection and expression of human recombinant adenovirus Ad5F35-IL-12 in the different kinds of human mononuclear macrophages. Methods The human recombinant adenovirus Ad5F35-IL-12 was used to infect human peripheral blood monocytes, pleural fluid macrophages as well as THP-1, U937 monocyte cell lines and their phorbol myristate acetate (PMA)-induced macrophages. 48 h later, green fluorescence was observed under the fluorescence microscope to detect the transfection efficiency. The expressions of IL-12 double-subunits (p35, p40) mRNA were tested by RT-PCR and the level of IL-12p70 protein in the cell culture supernatant was detected with ELISA. Results The human recombinant adenovirus Ad5F35-IL-12 successfully infected the human peripheral blood monocytes, pleural fluid macrophages, THP-1 monocytes, U937 monocytes, and THP-1 and U937 macrophages induced with PMA. All above infected mononuclear macrophages effectively secreted IL-12p70 protein, and they were listed from high to low of IL-12p70 protein level as pleural fluid macrophages, U937 and THP-1 macrophages induced with PMA, U937 monocytes, human peripheral blood monocytes and THP-1 monocytes. Conclusion The human recombinant adenovirus Ad5F35-IL-12 could infect different kinds of mononuclear macrophages, and IL-12 p70 protein could be successfully expressed in cell supernatants.

Objective: To assess how high ligation of varicocele improves sperm DNA integrity in patients with asthenospermia., Methods: The DNA fragmentation index (DFI) and semen analysis were conducted in 30 subjects with normal sperm samples, and the parameters were used as references. Fifty-six patients from the Department of Urology of the Second Affiliated Hospital of Chongqing Medical University from April 2009 to April 2011 all signed the informed consent. Semen was collected 1 week before the high ligation of varicocele and 3 months after the surgery. We compared the change of the integrity of sperm DNA and semen., Results: Three months after the high ligation of varicocele, DFI and semen indexes significantly improved (P<0.05), but no significant difference was found between open surgery and laparoscopic surgery, unilateral varicocele and bilateral varicocele and Grade I, Grade II, Grade III varicocele (P>0.05). Six months later, 27 spouses were pregnant out of the 53 surgical patients (50.9%). DFI of the pregnancy group and the non-pregnancy group was (13.90±9.70)% and (20.10±10.27)%, with significant different (P<0.05)., Conclusion: Varicocelectomy can improve the sperm DNA integrity in patients with asthenospermia, whose effect is not related to surgical approach, unilateral or bilateral varicocele or varicocele grade.

Objective: To investigate the effect of iron overload on experimental immunological liver injury in rats and the roles of losartan (LOS), which is the selective antagonist of angiotensin II receptor subtype AT1., Methods: Fifty male Wistar rats were divided by random into five groups (control, liver injury, liver injury + LOS, liver injury + ID and liver injury + ID + LOS). Immunological liver injury model was reproduceed by intravenous injection of BCG (Bacilli Calmette Guein) and then lipopolysaccharide (LPS). Iron overload model was created by intraperitoneal injection of iron dextran (ID). Serum iron (SI), transferrin (TRF), total protein (TP), the activity of asparatate aminotransferase (AST) and malondialdehyde (MDA) and liver iron (HIC) were tested. The expression of bcl-2 and Bax and the bax/bcl-2 ratio in hepatocyte were tested by flow cytometric analysis. Apoptotic index (AI) and proliferative index were also calculated., Results: (1) In comparison with blank control group, the activity of serum AST was higher. Serum TP and TRF were lower in liver injury animals. Liver MDA increased significantly and along with a lower SOD activity. The expression of Bax in liver injury group was significantly higher than that in control group. The bax/ bcl-2 ratio and AI increased significantly in liver injury group. (2) Compared with liver injury group, the animals treated with ID showed an increase of serum AST activity, increased MDA and the expression of bax, the bax/bcl-2 ratio and AI. HIC was higher than the control group. (3) Compared with liver injury group, the activity of serum AST was lower and TRF was higher, MDA was reduced and SOD activity increased in animals treated with LOS. The expression of bcl-2 was increased, bax/bcl-2 ratio and AI decreased in this group. (4) In comparison with ID treated liver injury animals, the activity of AST and the content of MDA, and TRF increased in the animals treated with ID plus LOS., Conclusion: The immunological liver injury could be aggravated by iron overload through catalyzing lipid peroxidation and facilitating the apoptotic process of hepatocyte. Angiotensin faciliates in this kind of liver damage.

We developed the recombinant green fluorescent protein gene yeast cell to screen estrogenic compounds based on two episomal vectors. In the expression vector the expression of human estrogen receptor alpha(hERalpha) was driven by 3-glyceraldehydephosphate dehydrogenase (GPD) promoter; in the reporter vector the expression of the yeast enhanced green fluorescent protein (yEGFP) gene was under the control of the estrogen response element (ERE). The vectors were transformed into yeast cell (W303-1A) to construct GFP recombinant yeast cell. Incubation of the yeast cell with various concentrations of the estrogenic compounds led to expression of the reporter gene product GFP in a dose dependent manner. Compared to other yeast bioassays, the yeast cell for environmental estrogen bioassay based on yEGFP reporter gene did not need cell wall disruption or the addition of a substrate or reagent. This yEGFP assay was performed completely in 96 well plates. So this test system can be used as a rapid and high throughput system for screening estrogenic chemical products, which has the characteristics of the sensitivity, reproducibility and cheapness.

Objective: To recognize the characteristics of desmoplastic small round cell tumor (DSRCT) and improve the standard of diagnosis., Methods: We retrospectively reviewed the clinical data on the treatment of 2 patients with DSRCT in terms of their conditions, tissue sources, pathologic characteristics, immunohistochemical methods, clinical manifestation, diagnosis, treatment and prognosis., Results: Clinical manifestations were complicated. The 2 patients were mis diagnosed before operation. Their tumors consisted of irregular nests of small and round cells, with nuclear hyperchromatism and scant cytoplasm embedded in a plenty of fibrous connective tissues. The edge of the nest was clear, with different sizes and shapes. Immunohistochemically, the 2 patients were positive for CK or EMA, NSE, des and vim of the epithelium, nerve, muscle and interstitial. They died 9 months after operation., Conclusions: The tumor may occur in the abdomen, pelvic cavity and other sites, with different clinical manifestations. Routine examination should be replaced by immunohistochemical test for correct diagnosis of the tumor. Prognosis of most patients is not good.