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Spread of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae Clinical Isolates from Patients in Bobo-Dioulasso, Burkina Faso
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作者 Kobo Gnada Michel Kiréopori Gomgnimbou +4 位作者 Armel Moumouni Sanou Louis Robert W. Belem Azouman Da Arnaud Quetin Sanou Do Malick Soufiane Sanou 《Journal of Biosciences and Medicines》 2025年第1期394-405,共12页
Antimicrobial resistance (AMR) is one of the top 10 threats to global health and it is estimated around 10 millions of deaths per year are associated with AMR until 2050. Burkina Faso is also facing the emergence and ... Antimicrobial resistance (AMR) is one of the top 10 threats to global health and it is estimated around 10 millions of deaths per year are associated with AMR until 2050. Burkina Faso is also facing the emergence and spread of AMR of several bacteria resistant strains such as those of public health concerns under surveillance Enterobacteriaceae. The aim of this study was to assess the prevalence of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE) clinical isolates from patients attending the bacteriology laboratory of the Centre MURAZ in Bobo-Dioulasso, Burkina Faso. Clinical isolates from urine, pus, stool, and semen were collected from April to June 2017. Identification and antibiotic susceptibility testing were performed using the VITEK 2 compact automated system according to EUCAST version 2015 recommendations. ESBL detection was then performed on the Muller-Hinton medium using the combined disc method. One hundred (100) strains of Enterobacteriaceae were isolated from 100 patients, including 52% of ESBLS. Escherichia coli (E. coli) was the most commonly isolated ESBL [(84.62, 44/72) ESBL], followed by Klebsiella spp. [(40%, 06/15) ESBL], then Enterobacter spp. [(40%, 2/5) ESBL]. Risk factor analysis revealed that ESBL-PE infection was frequently found in pus samples (P = 0.042;[OR] = 3.16;95% [CI] = 1.04 - 9.61) and that E. coli was the strain most likely to harbour ESBL (P = 0.008;[OR] = 3.60;95% [CI] = 1.40 - 9.31). This study reports a high prevalence of ESBL-PE associated with strong resistance to quinolones and cotrimoxazole (over 80%), which calls for increased surveillance of these superbugs, the adoption of a rational antibiotic prescription policy, and rigorous hygiene measures to prevent the spread of these multi-resistant bacteria. 展开更多
关键词 ENTEROBACTERIACEAE ESBL RESISTANCE ANTIBIOGRAM PHENOTYPES Burkina Faso
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In Silico Inhibitory Potential of Isolated Molecules of Scoparia dulcis L. (Scrophulariaceae) on SARS-CoV-2 Main Protease Mpro
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作者 Moussa Ouedraogo Windbedema Prisca Ouedraogo +5 位作者 Hermann W. Yameogo Inna T. Traore Raïnatou Boly Noufou Ouedraogo Rasmané Semde Sylvin Ouedraogo 《Pharmacology & Pharmacy》 2025年第2期31-51,共21页
Background: The Coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 coronavirus, remains a global threat despite lifting the health emergency. Scientists from all continents have been mobilized to d... Background: The Coronavirus disease 2019 (COVID-19) pandemic, caused by the SARS-CoV-2 coronavirus, remains a global threat despite lifting the health emergency. Scientists from all continents have been mobilized to develop vaccines and medicines for prevention and cure. In Burkina Faso, traditional healers proposed using Scoparia dulcis L., a medicinal plant, to manage COVID-19. Method: In silico screening offers a quick drug-likeness evaluation of Scoparia dulcis L.-isolated biomolecules toward SARS-CoV-2 targets, such as Mpro protease. A review of the literature retrieved 35 biomolecules isolated from Scoparia dulcis. The potential interactions of these biomolecules with the amino acid residues of the SARS-CoV-2 Mpro protease were visualized. Affinities and probable oral route delivery were assessed using reference molecules such as remdesivir and nelfinavir. Results: The screening allowed the retention of 20 hit molecules, which had a better affinity for the target than the reference molecules remdesivir and nelfinavir, and analysis of the results identified height lead molecules with a significant interaction with the Mpro protease and being druggable. There are six flavonoids: cirsimarin, cynaroside, hydroxy-tetramethoxyflavone, gossypetin, luteolin, vitexin, one diterpene, glutinol, and one glycoside, eugenyl-glucoside. These molecules interact with methionine 6 and tyrosine 126 of SARS-CoV-2 Mpro. These two amino acids are essential for the dimerization of Mpro protease. Inhibitory action on Mpro protease can be expected from these biomolecules. Conclusion: Scoparia dulcis L. could help manage COVID-19 because it contains biomolecules that can inactivate SARS-CoV-2 Mpro. 展开更多
关键词 COVID-19 Molecular Docking Mpro Biomolecules Scoparia dulcis
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CHARACTERISTICS OF MUCINS AND CEA IN GLOBOID DYSPLASTIC CELLS OF HUMAN STOMACH AND ITS RELATIONSHIP WITH SIGNET RING CELL CARCINOMA
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作者 刘树卿 张荫昌 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1990年第2期38-45,共8页
Fourty-three cases of globoid dysplasia and signet ring cell carcinoma were stained by mucin and CEA (ABC method). It was found that there were three kinds of mucins (neutral, sialo and sulphomucin in both globoid dys... Fourty-three cases of globoid dysplasia and signet ring cell carcinoma were stained by mucin and CEA (ABC method). It was found that there were three kinds of mucins (neutral, sialo and sulphomucin in both globoid dysplastic cells and signet ring cells. The percentages of the three kinds of mucins seen in the two kinds of cells were not much different. It was indicated that the altered mucins in the gastric epithelial cells must be a sign of dedifferentiation of the cells and the results of malfunction. The globoid dysplasia type I mainly contained neutral mucin, whereas type II, the acid mucin was predominant, especially the sulphomucin. The CEA positive reaction became stronger as the atypia being remarkable, and the characteristics of distribution of CEA positive particles were similar in the two kinds of cells namely, randomly or disorderly in the cells. Based on the analysis of the results, a conclusion can be made that the variety of mucins in globoid dysplastic cells can be used as a reference point in classification and is not much significant in grading, but the amount of CEA positive matter can be a reference point in grading. The globoid dysplasia is such a lesion with special features in morphology and function manifested in the process of de-differentiation towards signet ring cell carcinoma following the successive action of carcinogens upon the cells of gastric epithelium. 展开更多
关键词 CEA CHARACTERISTICS OF MUCINS AND CEA IN GLOBOID DYSPLASTIC CELLS OF HUMAN STOMACH AND ITS RELATIONSHIP WITH SIGNET RING CELL CARCINOMA
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Pseudomonas brassicacearum的数量分布差异及生物防治小麦全蚀病和油菜根腐病(英文) 被引量:1
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作者 P.R.HARVEY R.A.WARREN +1 位作者 W.ACHOUAK M.H.RYDER 《山东科学》 CAS 2005年第3期50-62,共13页
通过3种PCR技术测定基因特征和测定3种生化特征,对来自南澳洲两块对比小麦田土壤中的Pseudomonasbrassicacearum种群的菌株进行了分析研究。结果显示,两种不同土壤和两种不同根部区域(根表和根际),该种群具有高度多样性,其基因型和基因... 通过3种PCR技术测定基因特征和测定3种生化特征,对来自南澳洲两块对比小麦田土壤中的Pseudomonasbrassicacearum种群的菌株进行了分析研究。结果显示,两种不同土壤和两种不同根部区域(根表和根际),该种群具有高度多样性,其基因型和基因组也具有显著差异(P<0.05)。所分离到的菌株中,四分之三具有独特的基因组,90%以上的基因组是其原种群所独具有的。所有菌株的基因组的平均同源性比较低(22%),聚类分析不能证明来自不同小麦田和不同根部区域的菌株具有亲缘性。聚类分析显示,种群内的基因流动是受到限制的,菌株基因组的差异是由于基因的随机漂流引起的,由根表得到的基因型是与所采集的对比土壤相关联的。有三分之一的菌株检测到了2,4二乙酰基均苯三酚(PhlD)生物合成基因,这些菌株形成了一相关联的组群(同源性为60%)。4株产生PhlD的菌株(两种野生型,表型不同)对小麦全蚀病和腐霉引起的油菜根腐病具有显著的防治效果,展现出了对这类病原菌引起的根部病害的防治潜能。 展开更多
关键词 PSEUDOMONAS brassicacearum 遗传多样性 生物防治 全蚀病 PYTHIUM
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DISTRIBUTION AND ULTRASTRUCTURAL LOCALIZATION OF CARCINOEMBRYONIC ANTIGEN (CEA) IN SIGNET RING CELLS OF GASTRIC CANCER
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作者 杨光霖 董聿明 +2 位作者 吴继锋 胥爱莲 张平 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第4期36-39,共4页
The distribution and ultrastructural localization of CEA in signet-ring cells of 15 gastric cancer specimens were observed by PAP and immunoelectron microscopic methods. The mechanism of abnormal distribution of CEA i... The distribution and ultrastructural localization of CEA in signet-ring cells of 15 gastric cancer specimens were observed by PAP and immunoelectron microscopic methods. The mechanism of abnormal distribution of CEA in the signet-ring cell and its biological significance are discussed. The results showed that the CEA positive rate in signet-ring cells was 100% with the polarity lost in distribution. Under the light microscope, the CEA stain patterns were of two types: cytoplasmic and membranous types. The former was predominant. Under the electron microscope, most of the CEA was distributed on the cell membrane and cytoplasm. CEA was found in intracellular membranous structure of the cancer cells, especially in protein synthesis and transport organellae (RER, Golgi Complex etc.). The synthesis of CEA in cancer cells increased, yet its elimination was somewhat hampered. The result was that the RER became extended and were full of CEA (+) material. In the free signet-ring cell, there was a small and short contact plane. The tight junction was severed as the cell junction reduced. The antigenic determinant of CEA was glycoprotein. The abnormal distribution of CEA in signet-ring cells might be the morphologic reflection of the glycosylation of surface glycoprotein of tumor cells. 展开更多
关键词 CEA DISTRIBUTION AND ULTRASTRUCTURAL LOCALIZATION OF CARCINOEMBRYONIC ANTIGEN IN SIGNET RING CELLS OF GASTRIC CANCER
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Anti-Inflammatory and Antioxidant Properties of the Aqueous Extracts of the Leaves of Opilia amentacea (Opiliaceae)
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作者 Rainatou Boly Abdoul Gilchrist Laurent Boly +9 位作者 Wendkouni Leila Marie Esther Belem-Kabré Kadiatou Tata Traoré Boukaré Kaboré Ollo Youl Latifatou Sawadogo Mathieu Nitièma Moumouni Koala Noufou Ouédraogo Estella Noëla Hoho Youl Maminata Traoré-Coulibaly 《Pharmacology & Pharmacy》 2023年第9期329-347,共19页
Opilia amentacea (Opiliaceae) is a woody plant with multiple medicinal claimed effects. The present study aimed to assess the anti-inflammatory and antioxidant activities of the decoction and macerate extracts from th... Opilia amentacea (Opiliaceae) is a woody plant with multiple medicinal claimed effects. The present study aimed to assess the anti-inflammatory and antioxidant activities of the decoction and macerate extracts from the leaves of Opilia amentacea. Moreover, acute toxicity and phytochemical analysis were performed. The acute toxicity was evaluated on NMRI mice at 2000 mg/kg bw. The anti-inflammatory activity was studied using the carrageenan-induced mouse paw edema and the lipoxygenase inhibition assay. The radical scavenging (DPPH and ABTS), ferric-reducing antioxidant power (FRAP), and lipid peroxidation (LPO) assays were used to measure the antioxidant capacity of the extracts. Qualitative and quantitative methods served for identifying and quantifying the extract’s phytoconstituents. The decoction demonstrated low acute toxicity;the lethal dose was therefore estimated to be superior to 2000 mg/kg bw. The extracts significantly reduced the mouse paw’s thickness at 600 mg/kg bw. The extracts developed weak radical scavenging and lipid peroxidation inhibitory effects. However, the macerate showed a high ability (664.90 ± 0.71 mol Ascorbic Acid Equivalent/g dry extract) to reduce the ferric ions. Saponins, sterols, triterpenes, and flavonoids were qualitatively detected in the two extracts. Total phenolics (TP) and total flavonoids (TF) were found abundant in the extracts, especially the decoction (TP content (TPC) = 94.03 ± 2.66 mg GAE/g;TF content (TFC) = 35.05 ± 0.32 mg QE/g). Strong positive correlations existed between ferric-reducing capacity and TPC (r = 0.959) for the macerate, while TFC was mainly involved in the DPPH radical scavenging of the two extracts. Instead, most correlations were negative between the polyphenol compounds and the anti-inflammatory assays. The results indicate potent in vivo anti-inflammatory and in vitro antioxidant effects of the aqueous extracts from the leaves of Opilia amentacea. Further studies are needed to find the anti-inflammatory and antioxidant effects mechanism. 展开更多
关键词 Opilia amentacea Aqueous Extracts Acute Toxicity ANTI-INFLAMMATORY ANTIOXIDANT
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Phytochemical Analysis and Contractile Effects of Aqueous and Hydroethanolic Extracts of Anastatica hierochuntica L. (Brassicaceae) on the Isolated Uterus of Mice 被引量:1
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作者 Belem-Kabré Wendkouni Leila Marie Esther Nitiéma Mathieu +10 位作者 Odjo Blondine Saïdath Maman Noura Oumarou Yaro Boubacar Kaboré Boukaré Somda Gaëtan Donzéo Traoré Tata Kadiatou Koala Moumouni Ilboudo Sylvain Ouédraogo Moussa Kabré Elie Ouédraogo Noufou 《Pharmacology & Pharmacy》 2023年第8期252-270,共19页
Background: Anastatica hierochuntica L. (Brassicaceae) has been claimed to treat various conditions, including complicated childbirth. The principal objective of this research was to provide scientific evidence on the... Background: Anastatica hierochuntica L. (Brassicaceae) has been claimed to treat various conditions, including complicated childbirth. The principal objective of this research was to provide scientific evidence on the contractile effect of the aqueous and hydroethanolic extracts of the whole plant from A. hierochuntica during labor. Method: Qualitative and quantitative methods helped identify and quantify the phytoconstituents in both extracts. The antioxidant activity was studied using four standard methods (ABTS, DPPH, FRAP, and LPO). Results: The inhibitory power of the extracts on pro-inflammatory enzymes such as 15-lipoxygenase and phospholipase A<sub>2</sub> was determined. The contractile effects of the extracts were evaluated using isolated pregnant mice uteri. Steroids, triterpenoids, flavonoids, tannins, coumarins, and reduced compounds were identified in both extracts. The hydroethanolic extract exhibited higher content of hydrolyzable tannins (15.07 ± 0.24 mg tannic acid equivalent/g) than the aqueous decoction (11.8 ± 0.69 mg TAE/g). The extracts demonstrated the ability to scavenge DPPH and ABTS radicals, reduce ferric ions, and inhibit especially lipid peroxidation. No significant difference was noted in the phospholipase inhibition between the extracts and betamethasone. The hydroethanolic extract displayed the most significant anti-lipoxygenase activity with an IC<sub>50</sub> value of 55.82 ± 1.15 μg/mL. The lethal dose (LD<sub>50</sub>) of extracts was estimated to be superior to 2000 mg/kg body weight (bw). The ability of the samples to produce one cm amplitude of contraction at 50% effective concentrations (EC<sub>50</sub>) was 5.33 × 10<sup>−8</sup> ± 0.32 mg/mL for oxytocin, 1.51 ± 0.08 mg/mL for aqueous extract and 3.57 ± 0.61 mg/mL for hydroethanolic extract. Conclusion: These findings could provide evidence for using Anastatica hierochuntica to facilitate childbirth. 展开更多
关键词 Anastatica hierochuntica PHYTOCONSTITUENTS ANTIOXIDANT ANTI-INFLAMMATORY Uterine Contractility
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Acute Oral Toxicity and Vasorelaxant Effects of Hydroethanolic Extract from Lannea microcarpa Engl. & K. Krause (Anacardiaceae) Trunk Barks in Mice Aortas: Possible Involvement of Intracellular Ca 2+ Mobilization
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作者 Mathieu Nitiéma Bertrand Kafando +12 位作者 Windingoudi Rimwagna Christian Ouédraogo Bibata Sawadogo Boukaré Kaboré Wendkouni Leila Marie Esther Bélem-Kabré Tata Kadiatou Traoré Jean Claude Romaric Pingdwindé Ouédraogo Salfo Ouédraogo Lazare Belemnaba Aristide Traoré Moussa Ouédraogo Noufou Ouédraogo Bondo Félix Kini Sylvin Ouédraogo 《Pharmacology & Pharmacy》 2023年第12期530-549,共20页
Lannea microcrapa Engl. & K. Krause (Anacardiaceae) is a fruit and medicinal plant widely used in Burkina Faso. This plant is traditionally used in the treatment of hypertension. The aim of the present study was t... Lannea microcrapa Engl. & K. Krause (Anacardiaceae) is a fruit and medicinal plant widely used in Burkina Faso. This plant is traditionally used in the treatment of hypertension. The aim of the present study was to evaluate the vasorelaxant effects of the hydroethanolic extract from Lannea microcarpa trunk barks (HE_ELM) on the aorta isolated from NMRI mice. Phytochemical screening by HPTLC, assay of phenolic and flavonoid compounds, assessment of antioxidant activity (DPPH, ABTS, FRAP, and LPO), and myography of HE_ELM (1 - 2000 μg/mL) on mice thoracic aortas in the presence and absence of endothelium were carried out. Endothelium-dependent and endothelium-independant vasodilation were assessed by cumulative addition of Ach (1 nM - 10 μM) on aortic rings precontracted with the thromboxane analogue A2 agonist, 9,11-dideoxy9α,11α-methanoepoxy PGF2α (U46619). L-NAME was used to verify the involvement of NO production in the relaxation mechanism of the extract. Acute oral toxicity of HE_ELM was also evaluated. A phytochemical study revealed the presence of tannins, flavonoids, sterols and triterpenes, saponosides, and high levels of total phenolics and flavonoids. These compounds are thought to be responsible for the extract’s antioxidant and vasorelaxant properties. HE_ELM demonstrated significant antioxidant potential and induced aortic relaxation. Indeed, pharmacological parameters gave EC<sub>50</sub> values ranging from 596.45 ± 95.82 μg/mL to 749.48 ± 133.40 μg/mL and Emax values from 85.51% ± 9.59% to 96.81% ± 8.60% for the three conditions of vasodilation of the extract (p > 0.05). A complete antagonism of the contractile effect of U46619 was noted with 1 mg/mL HE_ELM. These results suggest that HE_ELM induces aortic relaxation through a concentration-dependent, endothelium-independent mechanism, possibly involving intracellular calcium mobilization of vascular cells. Acute oral toxicity tests of HE_ELM (2000 mg/kg) showed no mortality or adverse effects, suggesting the extract’s safety and potential as a therapeutic agent for hypertension. This discovery scientifically validates the use of the plant in alternative medicine to treat hypertension. 展开更多
关键词 Lannea macrocarpa Hydroethanolic Extract PHYTOCONSTITUENTS Antioxidant Vasorelaxant Effects Safety
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Acute Toxicity and Anthelmintic Effects of Gomphrena serrata L. (Amaranthaceae) Extracts on Adult Worms and Eggs of Haemonchus contortus
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作者 Hippolyte Ouedraogo Mohamed Bonewendé Belemlilga +6 位作者 Aristide Traore Gilchrist Abdoul Laurent Boly Félicité Moyenga Gueswindé Geoffroy Ouedraogo Sylvain Ilboudo Lazare Belemnaba Sylvin Ouedraogo 《Pharmacology & Pharmacy》 2024年第5期207-221,共15页
Gomphrena serrata L. (Amaranthaceae) is a medicinal plant widely used traditionally in rural areas to treat many diseases, including gastrointestinal helminthiasis of small ruminants. This work aims to estimate the pl... Gomphrena serrata L. (Amaranthaceae) is a medicinal plant widely used traditionally in rural areas to treat many diseases, including gastrointestinal helminthiasis of small ruminants. This work aims to estimate the plant extracts phytochemical potential and study the activities of the aqueous decoction (GS_AD), aqueous macerate (GS_AM), and hydroalcoholic macerate (GS_HEM) of Gomphrena serrata extracts on two developmental stages (eggs and adult worms) of Haemonchus contortus. Phytochemical screening was carried out. The acute toxicity test was performed according to the Organisation for Economic Co-operation and Development (OECD) test guideline 423. The Haemonchus contortus eggs hatching inhibition test was performed left to incubate for 48 hours in the presence of the different plant extracts at increasing concentrations of 0.125;0.25;0.5;0.625;1;2;3 mg/mL. For the motility inhibition test on adult worms, the worms were contacted with the extracts at concentrations of 0.75;1;1.25;1.5;2;3;4 mg/mL and left to incubate for 24 hours. Albendazole and levamisole were used as standard. Phytochemical screening revealed the presence of tannins, saponins, reducing compounds, coumarins and derivatives, anthocyanins, steroids, triterpenes, and flavonoids. An acute toxicity study showed that the oral LD<sub>50</sub> value of G. serrata was estimated to be 5000 mg/kg. All extracts showed an effect on both stages of parasite development. The hatching inhibition rate was 100% from 3 mg/mL for all three extracts. The rate of inhibition of motility was 100% from 4 mg/mL for each extract. HEM is more efficient on eggs and Haemonchus contortus adult worms than other extracts with IC<sub>50</sub> of 0.457 mg/mL and LC<sub>50</sub><sub> </sub>of 1.329 mg/mL, respectively. These results suggest that Gomphrena serrata, a plant used by farmers, has anthelmintic properties. 展开更多
关键词 Gomphrena serrata Haemonchus contortus ANTHELMINTIC In Vitro
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积石山M_(S)6.2、乌什M_(S)7.1地震前后地电场变化特征研究
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作者 范莹莹 安张辉 +1 位作者 吴优 林毅 《地震工程学报》 北大核心 2026年第1期197-204,共8页
利用积石山M_(S)6.2地震和乌什M_(S)7.1地震震中周围的地电场台站观测数据,研究地震发生前后地电场能谱值变化。结果表明:(1)在积石山M_(S)6.2地震发生前,武胜驿、松山和平凉等台观测到地电场低频成分能谱值有显著增大的现象;(2)乌什M_(... 利用积石山M_(S)6.2地震和乌什M_(S)7.1地震震中周围的地电场台站观测数据,研究地震发生前后地电场能谱值变化。结果表明:(1)在积石山M_(S)6.2地震发生前,武胜驿、松山和平凉等台观测到地电场低频成分能谱值有显著增大的现象;(2)乌什M_(S)7.1地震发生前,乌什、温泉和乌鲁木齐等台均观测到地电场低频成分能谱值先增大后降低的明显变化;(3)初步分析认为,地震前地电场异常现象主要是由于震源孕育过程中激发的低频电磁辐射传播至台站所致。然而,测区地下介质的形变也可能激发局部区域的低频电磁辐射,这一因素同样不容忽视。 展开更多
关键词 积石山M_(S)6.2地震 乌什M_(S)7.1地震 地电场 能谱 变化特征
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井下短周期地震计方位角预处理参数
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作者 刘明辉 李江 +4 位作者 施鸿昊 周银兴 康璐璐 吴卫远 韩腾 《大地测量与地球动力学》 北大核心 2026年第2期178-183,共6页
海洋脉动波峰的频带处于井下短周期地震计速度平坦响应范围之外。本文运用传递函数,恢复低噪声短周期地震计记录的海洋脉动波峰,并将其作为计算井下短周期地震计安装方位角的信号源。为探究预处理参数对井下短周期地震计安装方位角计算... 海洋脉动波峰的频带处于井下短周期地震计速度平坦响应范围之外。本文运用传递函数,恢复低噪声短周期地震计记录的海洋脉动波峰,并将其作为计算井下短周期地震计安装方位角的信号源。为探究预处理参数对井下短周期地震计安装方位角计算结果合格率的影响,首先采用6组不同带宽的滤波器,对24 h连续数据进行预处理滤波;接着将连续数据划分为5种不同时间长度;随后运用相关方法计算井下短周期地震计的安装方位角;最后筛选出东西(EW)和南北(NS)方向平均相关系数大于0.995,且二者夹角不超过1.2°的安装方位角。结果显示,采用带宽为0.2~0.6 Hz的滤波器,对时长300 s的数据进行预处理滤波,再通过相关计算得到的安装方位角,其合格次数最多;并且合格次数在19:00—06:00期间明显多于在07:00—16:00期间。对比地表和井下短周期地震计安装方位角校正前后的地球背景噪声可知,校正前EW和NS方向并不重合,校正后二者完全重合,这验证了使用0.2~0.6 Hz的滤波器和时长300 s的这组预处理参数进行方位角计算的有效性。该预处理参数还可应用于井下甚宽带地震计的方位角校正计算及地表地震计之间对齐误差的测试。 展开更多
关键词 井下观测 短周期地震计 方位角 预处理参数
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基于地震矩守恒的断裂带最大震级及复发周期估算方法
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作者 陈璇 刘静 +3 位作者 姚文倩 徐晶 王世龙 杨婧蕾 《大地测量与地球动力学》 北大核心 2026年第1期94-105,114,共13页
梳理总结现有最大震级传统估算方法,指出这些方法仅基于观察到的地震活动数据,若最大地震的复发周期超出数据覆盖时期或地震活动率在更长时间尺度内波动,方法将失效。此外,传统方法在缺乏物理约束时,预测的最大事件震级可能随时间范围... 梳理总结现有最大震级传统估算方法,指出这些方法仅基于观察到的地震活动数据,若最大地震的复发周期超出数据覆盖时期或地震活动率在更长时间尺度内波动,方法将失效。此外,传统方法在缺乏物理约束时,预测的最大事件震级可能随时间范围的扩大而无限增长。为克服这些局限,介绍一种基于地震矩守恒的新模型。模型综合考虑了仪器记录、断层滑动速率、断层几何特征和地震活动等规律,假设地震活动符合G-R定律,通过模拟缺失的大地震及其余震来构建长期地震目录,并利用地震矩积累速率对最大震级进行物理约束,从而有效避免传统方法对数据观察期的依赖。应用该模型对阿尔金断裂带、昆仑断裂带和龙门山断裂带的最大震级(M_(max))及复发周期进行预测,结果与历史地震记录、古地震数据和滑动速率观测高度一致,验证了该模型的有效性。该研究结果为最大震级的估算提供了全新视角,并为缺乏完整历史记录地区的地震风险评估提供了重要工具。 展开更多
关键词 最大震级(M max) 复发周期 G-R定律 地震矩守恒 地震风险评估
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基于多频GNSS观测数据的2025年定日M_(W)6.8地震同震形变特征
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作者 董志华 孟国杰 +3 位作者 吴伟伟 魏聪敏 杨衍聪 王宇凡 《大地测量与地球动力学》 北大核心 2026年第2期155-161,共7页
基于2025年定日6.8级地震震中450 km范围内低频(30 s)、高频(1 Hz)及超高频(50 Hz)GNSS观测数据,利用精密单点定位(PPP)技术,获得该地震的同震静态位移场与动态波形。研究发现,低频GNSS同震静态位移场显示出震中区域具有最大40.0 mm的... 基于2025年定日6.8级地震震中450 km范围内低频(30 s)、高频(1 Hz)及超高频(50 Hz)GNSS观测数据,利用精密单点定位(PPP)技术,获得该地震的同震静态位移场与动态波形。研究发现,低频GNSS同震静态位移场显示出震中区域具有最大40.0 mm的西向永久位移,与区域构造应力场一致;高频GNSS同震波形捕捉到近场站点显著的动态位移峰值,XZZF(珠峰)站东西向位移达28.83 mm,但受动态效应影响,其与低频结果存在12.5 mm的偏差;超高频GNSS同震波形在远场记录到Love波与Rayleigh波,并识别出断层分段破裂的双脉冲特征。高频和超高频同震波形频谱分析结果表明,近场测站(如XZZF测站)能量主要集中于0.5~5 Hz,反映断层初始破裂特征,而远场测站(如XZRK测站)以低频面波(0.1~1 Hz)为主导,验证了多频GNSS数据的互补性。此外,超高频数据在捕捉地震波高频成分(>5 Hz)和瞬时破裂过程方面具有不可替代性,可为震源参数反演提供重要的观测数据约束。 展开更多
关键词 定日M_(W)6.8地震 高频GNSS 超高频GNSS 静态同震形变 动态同震波形
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基于GNA-ARMA模型的摆式倾斜仪传递函数辨识研究
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作者 左文涛 周云耀 吕永清 《大地测量与地球动力学》 北大核心 2026年第2期189-193,共5页
提出一种基于自适应高斯牛顿法(GNA)与自回归滑动平均(ARMA)模型相结合的系统辨识方法,建立摆式倾斜仪系统传递函数模型。通过GNA算法动态调整步长,优化系统参数估计,同时利用ARMA模型建模噪声特性抑制随机波动,并对系统辨识结果进行综... 提出一种基于自适应高斯牛顿法(GNA)与自回归滑动平均(ARMA)模型相结合的系统辨识方法,建立摆式倾斜仪系统传递函数模型。通过GNA算法动态调整步长,优化系统参数估计,同时利用ARMA模型建模噪声特性抑制随机波动,并对系统辨识结果进行综合分析。结果表明,相对较于单一GNA算法,结合ARMA模型后系统传递函数拟合精度从92.96%提升至95.53%,预测误差(FPE)由115.9降至47.28,有效提高了抑制系统外界噪声的能力,且零极点和残差分布验证系统传递函数具有较好的稳定性与可靠性。本文方法可以提升摆式倾斜仪系统传递函数辨识精度与鲁棒性,为仪器校准与性能优化提供支撑。 展开更多
关键词 传递函数辨识 自适应高斯牛顿法 ARMA模型 综合分析 摆式倾斜仪器系统
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饱和黏土动剪切模量和阻尼比研究现状分析
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作者 蔡润 王兰民 +2 位作者 郭鹏 彭涛 王谦 《地震工程学报》 北大核心 2026年第1期1-14,共14页
随着海上风电和油气作业的发展,饱和黏土的动剪切模量和阻尼比对海洋基础场地动力稳定性评价至关重要。近年来,针对饱和黏土动剪切模量和阻尼比的研究取得了一系列重要成果。通过对前人的研究成果进行整理和分析,分别从动剪切模量和阻... 随着海上风电和油气作业的发展,饱和黏土的动剪切模量和阻尼比对海洋基础场地动力稳定性评价至关重要。近年来,针对饱和黏土动剪切模量和阻尼比的研究取得了一系列重要成果。通过对前人的研究成果进行整理和分析,分别从动剪切模量和阻尼比的室内测试方法、影响因素及变化规律、预测模型等方面,系统地总结饱和黏土动剪切模量和阻尼比的国内外研究进展;同时,对比分析循环拉伸应力状态和不同循环应力路径对其的影响,并采用神经网络技术对现有研究成果进行厘定。综述可为海洋基础场地动力稳定性评价相关研究的深入开展提供参考。 展开更多
关键词 饱和黏土 动剪切模量 阻尼比 影响因素 预测模型
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鄂西及邻区弹性岩石圈厚度及其与地震分布
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作者 孟恒舟 杨光亮 +1 位作者 秦海涛 刘胜 《大地测量与地球动力学》 北大核心 2026年第2期171-177,共7页
为深入认识鄂西及邻区岩石圈力学结构的空间异质性及其与地震活动性的耦合,基于WGM2012重力场数据、Crust1.0模型数据及ETOP01地形数据,计算并分析了鄂西及邻区弹性岩石圈厚度(T_(e))及偏应力。结果显示:1)区内弹性岩石圈厚度呈显著空... 为深入认识鄂西及邻区岩石圈力学结构的空间异质性及其与地震活动性的耦合,基于WGM2012重力场数据、Crust1.0模型数据及ETOP01地形数据,计算并分析了鄂西及邻区弹性岩石圈厚度(T_(e))及偏应力。结果显示:1)区内弹性岩石圈厚度呈显著空间分异(5~50 km),扬子克拉通西缘的四川盆地及武陵倾覆等区域(T_(e)>30 km)表现为高强度稳定区,而江南造山带(T_(e)<20 km)则构成弹性岩石圈薄弱带;2)岩石圈有效厚度与地表热流值呈负相关性,武陵倾覆为冷岩石圈块体,其低热流值(<50 mW/m^(2))对应厚T_(e)特征;3)地震活动性受控于T_(e)与偏应力,四川盆地西缘兼具低T_(e)值与高偏应力背景(10~15 MPa),地震丛集,而江南造山带为低T_(e)且偏应力普遍小于3 MPa,地震事件较少。区域地震危险性评估需综合考虑弹性岩石圈厚度与偏应力场的耦合。 展开更多
关键词 弹性岩石圈厚度 偏应力 鄂西 重力异常
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分布式测震实时流数据容错系统应用研究
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作者 李杨 冯兵 +2 位作者 蔡寅 张秀萍 许利娜 《计算机应用与软件》 北大核心 2026年第2期64-70,146,共8页
为增强测震流式数据采集的容错纠错能力,提高数据处理的稳定性和可靠性,提出基于ZooKeeper的分布式测震实时流数据处理方法。构建ZooKeeper分布式服务架构;通过监听动作完成整个流程中的主备切换,并继续进行数据消费行为,实现服务注册... 为增强测震流式数据采集的容错纠错能力,提高数据处理的稳定性和可靠性,提出基于ZooKeeper的分布式测震实时流数据处理方法。构建ZooKeeper分布式服务架构;通过监听动作完成整个流程中的主备切换,并继续进行数据消费行为,实现服务注册、服务加载、服务容错、策略调度功能。测试结果表明该方法下系统平均每小时服务修复时间(MTTR)降低98.4%,平均每小时故障间隔时间(MTTF)提升33.5%,对于故障场景下数据完整率提升20%,能够较好解决测震流式数据面临的稳定性和可靠性困难,具备区域地震台网技术推广应用潜力。 展开更多
关键词 实时流数据 容错纠错 协调服务 服务模型
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基于SIP-LOF算法的地形变仪器监测数据异常识别方法
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作者 冯晓晗 杨江 《地震工程学报》 北大核心 2026年第1期242-250,共9页
为进一步检测地形变仪器的异常数据,提升仪器数据可用率及运维人员故障初步判别效率,文章提出一种基于数据挖掘的序列重要点-局部异常因子(SIP-LOF)算法。将地形变仪器的原始观测序列分割成子序列,通过计算序列中每个点的离群距离和局... 为进一步检测地形变仪器的异常数据,提升仪器数据可用率及运维人员故障初步判别效率,文章提出一种基于数据挖掘的序列重要点-局部异常因子(SIP-LOF)算法。将地形变仪器的原始观测序列分割成子序列,通过计算序列中每个点的离群距离和局部异常因子等,判断该数据点是否为离群点,进而量化每个数据点的异常程度,实现对前兆形变观测中自然干扰、设备故障、地震前兆等典型事件的异常检测。研究结果表明,相较于传统方法,该方法针对多个台站前兆数据的异常检测均有较好的检测效果,异常类型覆盖面更广;并且,当LOF限值为2.5时平均异常判定准确率最高,对前兆数据的处理工作具有积极意义。 展开更多
关键词 观测数据 典型事件 异常检测 局部异常因子
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CG6相对重力仪静态漂移特性分析
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作者 李忠亚 胡敏章 《大地测量与地球动力学》 北大核心 2026年第2期184-188,共5页
深入认识CG6相对重力仪的静态漂移特性有利于获得高质量的相对重力观测数据。利用三亚地震台相邻2个重力观测墩上的CG6-90相对重力仪和iGrav-56超导重力仪65 h观测数据,设计3种方案计算CG6-90相对重力仪的静态漂移率。结果表明,CG6-90... 深入认识CG6相对重力仪的静态漂移特性有利于获得高质量的相对重力观测数据。利用三亚地震台相邻2个重力观测墩上的CG6-90相对重力仪和iGrav-56超导重力仪65 h观测数据,设计3种方案计算CG6-90相对重力仪的静态漂移率。结果表明,CG6-90相对重力仪的静态线性漂移率为-8.861±0.035μGal/h,仪器观测数据存在-1~1μGal重力变化的非线性漂移现象,并且计算CG6相对重力仪静态漂移率时有必要进行固体潮、海潮和气压变化等因素导致的重力变化改正。 展开更多
关键词 CG6重力仪 静态漂移 iGrav超导重力仪 重力改正 海潮
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