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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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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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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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陆态网络基准站北斗全星座观测数据定位精度分析 被引量:1
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作者 张风霜 刘浩 李文一 《测绘科学》 北大核心 2025年第5期11-23,共13页
为评估北斗卫星导航系统全星座观测数据的定位精度,依托陆态网络试验性并行观测项目8个基准站的同步、共址GPS/BDS观测数据,利用高精度解算软件GAMIT/GLOBK分别独立处理了2023年365 d的GPS/BDS数据,并进行了对比分析。结果表明:BDS测站... 为评估北斗卫星导航系统全星座观测数据的定位精度,依托陆态网络试验性并行观测项目8个基准站的同步、共址GPS/BDS观测数据,利用高精度解算软件GAMIT/GLOBK分别独立处理了2023年365 d的GPS/BDS数据,并进行了对比分析。结果表明:BDS测站坐标北向、东向、垂向精度分别约为3.18、4.24、11.42 mm,仍低于GPS系统;BDS长基线(218~6135 km范围)水平分量重复性约为0.5~2 mm,垂向约为3~6 mm,基线长度相对重复性可达到10-10量级,BDS基线重复性优于GPS;随着北斗全星座系统的完善,BDS定位精度在持续提升,BDS基线相对定位精度已与GPS基本相当,BDS测站坐标水平和垂向分量定位精度与GPS的差距也进一步缩小为1~2 mm和2~5 mm。目前制约BDS定位精度的主要原因是北斗卫星定轨精度以及太阳光压和天线相位中心等误差改正模型的不完善。 展开更多
关键词 BDS 全星座 长基线重复性 定位精度 GPS
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积石山6.2级地震学校建筑典型震害特征及对人员疏散的启示 被引量:2
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作者 潘毅 陈子峰 +1 位作者 郭欣 林旭川 《地震工程学报》 北大核心 2025年第3期610-620,651,共12页
2023年12月18日,甘肃省积石山县发生6.2级地震。地震发生后,对处于不同烈度区的9所中小学及4个教学点内的15栋框架结构和24栋砌体结构进行调查与分析。调查结果显示,发生严重破坏的12栋建筑均为设置钢木屋架的单层砌体结构;框架结构仅... 2023年12月18日,甘肃省积石山县发生6.2级地震。地震发生后,对处于不同烈度区的9所中小学及4个教学点内的15栋框架结构和24栋砌体结构进行调查与分析。调查结果显示,发生严重破坏的12栋建筑均为设置钢木屋架的单层砌体结构;框架结构仅有少数发生中等破坏,其余均为轻微破坏。在一些主体结构相对完好的学校建筑中,非结构构件、构筑物的震害仍相对严重,对校内师生的人生安全和疏散路径畅通造成较大影响。基于现场震害调查结果,归纳出学校建筑及内部设施常见的破坏模式,总结校内师生疏散路径中“房间”“走廊”“楼梯”“户外”等主要环节存在的潜在安全隐患。结合本次地震中学校校园空间中存在的潜在安全隐患,建议可对非结构构件、设备与构筑物采取适当加固措施,以进一步提升震后学校师生的人员安全和疏散畅通性。 展开更多
关键词 积石山地震 震害调查 学校建筑 震害特征 人员疏散 人员安全
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水准观测到的大震前隆起异常——物理形变与几何形变
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作者 薄万举 张立成 +1 位作者 陈兆辉 徐东卓 《大地测量与地球动力学》 北大核心 2025年第10期991-996,1070,共7页
通过搜集中长期强震预测成果,对全球导航卫星系统(GNSS)与水准测量垂直形变之间的共性与差异进行深入分析,并探讨了大震前水准异常隆起的相关问题,包括水准异常波动及其与GNSS观测结果的差异。通过对多年精密水准测量数据进行分析,揭示... 通过搜集中长期强震预测成果,对全球导航卫星系统(GNSS)与水准测量垂直形变之间的共性与差异进行深入分析,并探讨了大震前水准异常隆起的相关问题,包括水准异常波动及其与GNSS观测结果的差异。通过对多年精密水准测量数据进行分析,揭示了大震前地面隆起的异常现象,并结合大震前重力异常的研究成果,对二者之间的关系进行了推演和分析。水准测量获得的垂直形变数据中,不仅涵盖了点位垂向几何形变的影响,还包含了局部重力水准面动态弯曲的信息,其量级可达2 mm以上。基于此,本文提出了物理形变与几何形变的概念。本文研究对于不同形变机理差异的正确理解、强震的中长期预测及形变异常监测方案的制定和决策具有重要的理论与实践意义。 展开更多
关键词 物理形变 几何形变 强震预测 水准面 重力异常 重力位
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色尔腾山山前断裂浅层地震勘探和钻探的新证据
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作者 杨杰 贺为民 +2 位作者 秦晶晶 宋晓鹏 刘庆 《大地测量与地球动力学》 北大核心 2025年第2期144-150,共7页
横跨色尔腾山山前断裂布设一条长10.77 km的浅层地震勘探测线L1,结果发现,色尔腾山山前断裂在剖面上清晰可见,其主断裂在上部存在分叉,由断层F_(P1.1)和F_(P1)组成,均为正断层,视倾向南;结合地质地貌调查认为,F_(P1.1)断层的最新活动时... 横跨色尔腾山山前断裂布设一条长10.77 km的浅层地震勘探测线L1,结果发现,色尔腾山山前断裂在剖面上清晰可见,其主断裂在上部存在分叉,由断层F_(P1.1)和F_(P1)组成,均为正断层,视倾向南;结合地质地貌调查认为,F_(P1.1)断层的最新活动时代为全新世。针对色尔腾山山前断裂的F_(P1)断层开展钻孔联合地质剖面探测,划分出Fa、Fb两个断层,结合光释光测年结果发现,断层Fa和Fb为全新世断层,其最新活动时代晚于2.5±0.6 ka BP。色尔腾山山前断裂在近地表呈叉状结构,是该断裂在晚第四纪具有多次活动的反映。 展开更多
关键词 色尔腾山山前断裂 活动断层 浅层地震勘探 钻孔联合地质剖面
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西藏定日6.8级地震同震及震前GNSS变形特征分析
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作者 朱爽 占伟 刘晓 《震灾防御技术》 北大核心 2025年第2期233-242,共10页
北京时间2025年1月7日9点5分,在我国西藏定日县发生了6.8级地震。利用震中周边GNSS连续观测数据反演获取同震位移场,结果表明,距离震中最近的测站为XZZF站,其同震位移量最大,南北向达到−17.14 mm,东西向达到−41.62 mm,基于震中周边3个... 北京时间2025年1月7日9点5分,在我国西藏定日县发生了6.8级地震。利用震中周边GNSS连续观测数据反演获取同震位移场,结果表明,距离震中最近的测站为XZZF站,其同震位移量最大,南北向达到−17.14 mm,东西向达到−41.62 mm,基于震中周边3个站点的同震位移数据特征分析,此次地震呈现出典型的正断型地震运动学特征;对GNSS站间基线时间序列及区域应变时间序列的系统性研究结果显示,登么错断裂(又称丁木错断裂)带处于显著的拉张运动状态;震前GNSS动态应变场的分析结果表明,该区域的面应变由挤压逐渐变为拉张趋势,量值较小,且始终处在拉张应变高值区边缘;块体模型计算得到申扎-定结裂谷的左旋滑动速率为(3.2±0.5)mm/a,伸展速率为(1.4±0.6)mm/a,GNSS剖面计算得到发震断层登么错的拉张滑动速率为(1.58±0.6)mm/a,左旋滑动速率为(1.49±0.7)mm/a,裂谷南段的运动速率相对于整个裂谷运动速率较小,且处于应变高值区边缘,未来仍有发生强震的可能。 展开更多
关键词 定日地震 GNSS 同震 应变场 滑动速率
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基于InSAR监测的鹤岗矿区地壳形变特征与冲击地压相关性研究
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作者 付兴 宋健康 +5 位作者 张拓 张宏伟 刘天昊 陈世威 金波 李玉 《煤炭科学技术》 北大核心 2025年第8期215-225,共11页
冲击地压是地质动力环境与开采工程扰动耦合作用的结果,矿区地壳形变特征是地质动力环境的重要影响因素之一,能够直观反映井下工作面开采上覆煤岩体结构受力变形-失稳的动态演化特征。而开采工程扰动又使得煤岩体的应力升高,能量积聚,... 冲击地压是地质动力环境与开采工程扰动耦合作用的结果,矿区地壳形变特征是地质动力环境的重要影响因素之一,能够直观反映井下工作面开采上覆煤岩体结构受力变形-失稳的动态演化特征。而开采工程扰动又使得煤岩体的应力升高,能量积聚,达到煤岩临界条件时,则易诱发能量的瞬时释放,造成冲击地压的灾害发生。因此,矿区区域地壳形变特征与冲击地压之间有密切的联系。为了深入分析矿区地壳形变特征与冲击地压微震能量事件的关联,以鹤岗矿区的InSAR监测数据为基础,研究了富力煤矿、兴安煤矿和峻德煤矿地表形变的时空演化特征,并以峻德煤矿17层三四区二段工作面为例,选取了该区域的10个点位的InSAR监测结果,将其平均地壳形变量特征与冲击地压微震总能量进行综合分析,定量确定了大能量微震事件发生与区域地壳形变的“时-空-强”特征。研究表明:峻德煤矿井田地壳垂直形变量与17层微震事件总能量变化趋势是一致性达到69%,在时间频度上有较高的一致性。选取典型时段(2020-12-02—2021-12-28)24次大能量微震事件发生的能量大小与震中距与10个监测点位的平均形变量进行皮尔森相关性分析,得出微震能量大小与平均形变量呈正相关,相关系数为0.56,震中距与平均形变量呈负相关,相关系数为-0.75,反映了地壳形变特征与冲击地压的空间和强度关系,说明了InSAR监测在时间、空间、形变量与微震监测的微震事件有较高的匹配度。 展开更多
关键词 冲击地压 INSAR 地壳形变特征 微震事件 震中距
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考虑恢复过程的桥梁抗震韧性评估方法
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作者 李廷辉 刘金龙 +2 位作者 李晓丽 王燕 计静 《振动与冲击》 北大核心 2025年第7期132-145,共14页
提出了一种考虑恢复过程的混凝土桥梁结构抗震概率韧性评估方法,该方法基于暴露在恶劣环境下的混凝土结构生命周期分析的一般方法,以各破坏状态下的时变抗震能力作为功能指标,将灾害发生后残余功能和恢复过程与地震事件发生的时间联系... 提出了一种考虑恢复过程的混凝土桥梁结构抗震概率韧性评估方法,该方法基于暴露在恶劣环境下的混凝土结构生命周期分析的一般方法,以各破坏状态下的时变抗震能力作为功能指标,将灾害发生后残余功能和恢复过程与地震事件发生的时间联系起来。通过对时变桥梁易损性模型进行抽样获得桥梁地震破坏样本,结合时变功能指标,采用遗传算法(genetic algorithm,GA)解决资源约束调度问题(resource constrained project scheduling problem,RCPSP),给出了桥梁震后的具体恢复过程,最终得到了桥梁结构服役期间的抗震韧性。结果发现,当不考虑时变功能时,计算得到的桥梁抗震韧性要明显大于考虑时变功能计算得到的抗震韧性,这样会高估桥梁抵抗地震灾害及从中恢复的能力,不利于震后恢复工作的展开。选取的控制时间(t_(h)-t_(0))要合理,如果使控制时间(t_(h)-t_(0))过小,计算得到的桥梁抗震韧性普遍为0,此时就不能很好地表达桥梁的抗震韧性。 展开更多
关键词 时变功能 抗震韧性 遗传算法(GA) 资源约束调度问题(RCPSP)
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低载荷下PTFE-不锈钢摩擦特性及力学模型研究
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作者 赵守江 戴君武 《工程科学与技术》 北大核心 2025年第3期42-50,共9页
在滑移隔震支座中,聚四氟乙烯(PTFE)和不锈钢所构成的摩擦副应用广泛,其摩擦特性是影响支座隔震效果的关键因素之一。为研究其在低载荷条件下的摩擦特性,通过滑动摩擦试验考察静摩擦系数和动摩擦系数随载荷变化的规律,以及动摩擦系数与... 在滑移隔震支座中,聚四氟乙烯(PTFE)和不锈钢所构成的摩擦副应用广泛,其摩擦特性是影响支座隔震效果的关键因素之一。为研究其在低载荷条件下的摩擦特性,通过滑动摩擦试验考察静摩擦系数和动摩擦系数随载荷变化的规律,以及动摩擦系数与速度的相互关系。建立PTFE-不锈钢的摩擦力模型,并结合振动试验和数值分析对该模型的准确性进行验证。此外,对比评估了该力学模型与库仑模型在预测摩擦行为方面的适用性。结果表明:静摩擦系数和动摩擦系数均与竖向载荷显著相关。当压强为0~0.5 MPa时,静摩擦系数随压强增大而大幅度降低;当压强为0.5~1.2 MPa时,静摩擦系数的降幅趋缓并基本稳定在0.045左右。对于动摩擦系数,当压强为0~2.0 MPa时,其随压强增大呈现出先减小后增大的趋势,且增速持续减缓;同一压强下,动摩擦系数随速度增大而增大,并在速度达到一定阈值后趋于稳定,而且不同压强下的上限值均接近0.202;动摩擦系数与速度的关系可用指数函数描述。在多次振动响应试验中,加速度时程曲线的重合度优于相对位移的重合度,但随着试验次数的增加,相对位移的重合度有所提高。通过对比位移变化量和加速度极值,验证了基于指数函数模型的理论分析值与试验值的高吻合度。相较于库仑模型,指数函数模型能更准确地反映低载荷下摩擦力的特征,也更适用于滑移隔震支座的动力响应分析。 展开更多
关键词 聚四氟乙烯(PTFE) 不锈钢 滑移隔震 力学模型 低载荷 摩擦系数
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基于流动重力控制的gPhone重力仪漂移修正方法研究
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作者 张源 崔庆谷 +4 位作者 黑贺堂 黄江培 周文敏 字承柱 陈阳 《地震研究》 北大核心 2025年第4期685-692,共8页
针对gPhone连续重力仪漂移修正困难的情况,收集2019年1月—2024年5月云龙地震台gPhone连续重力仪观测数据,采用流动重力数据控制的方法进行漂移修正,并与目前常用的小波滤波和多项式拟合修正方法进行比较,修正后的结果显示:①5.4 a累计... 针对gPhone连续重力仪漂移修正困难的情况,收集2019年1月—2024年5月云龙地震台gPhone连续重力仪观测数据,采用流动重力数据控制的方法进行漂移修正,并与目前常用的小波滤波和多项式拟合修正方法进行比较,修正后的结果显示:①5.4 a累计变化量从约1374×10-8 m/s 2降至69×10-8 m/s 2;②漂移修正结果与5阶多项式修正结果相似;③模型评价结果优于其他2种方法;④残差分布与5阶多项式修正结果接近。 展开更多
关键词 gPhone连续重力仪 流动重力 多项式 小波滤波 漂移修正
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直线导轨式隔震装置的设计与性能研究
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作者 赵守江 柏文 《地震工程学报》 北大核心 2025年第1期50-59,共10页
为确保馆藏文物的地震安全,研制出一款新型直线导轨式隔震装置,采用振动台试验和理论分析方法对其有效性进行验证。首先阐述装置的构造和工作机理,推导出装置的刚度和黏滞阻尼系数表达式;然后制作原型样机并通过振动台试验验证其隔震有... 为确保馆藏文物的地震安全,研制出一款新型直线导轨式隔震装置,采用振动台试验和理论分析方法对其有效性进行验证。首先阐述装置的构造和工作机理,推导出装置的刚度和黏滞阻尼系数表达式;然后制作原型样机并通过振动台试验验证其隔震有效性;最后依据所测基本参数,建立装置单向水平隔震系统的动力方程并开展数值分析。结果表明,该隔震装置结构简单、性能可靠,具有摩擦系数低、起滑加速度阈值小,以及刚度和阻尼灵活可调的特点;它可以在满足位移限值的情况下达到设定隔震目标,且自复位效能力强、残余位移小。装置理论分析结果与试验实测动力响应吻合程度高,且吻合程度随地震动峰值的提高而进一步增强。该理论分析方法可以用于指导装置参数设计和隔震性能评估。 展开更多
关键词 文物 隔震 直线导轨式 振动台试验 数值模拟
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