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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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Thriving across seawater depths:How blue light shapes a large PSI supercomplex and specific photosynthetic traits in the seagrass Posidonia oceanica
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作者 Quentin Charras-Ferroussier Charlie Mathiot +7 位作者 Dmitry A.Semchonok Eduard Elias Ahmad Farhan Bhatti Re´gine Lebrun Dorian Guillemain Marina I.Siponen Roberta Croce Colette Jungas 《Plant Communications》 2026年第1期201-216,共16页
Seagrasses are marine flowering plants that perform oxygenic photosynthesis both under high,white sunlight and under low,blue-green light,conditions fundamentally different from those experienced by land plants.Thus f... Seagrasses are marine flowering plants that perform oxygenic photosynthesis both under high,white sunlight and under low,blue-green light,conditions fundamentally different from those experienced by land plants.Thus far,the adaptation of seagrass photosynthetic machinery to this underwater light gradient remains poorly understood.Here,we investigate the Mediterranean seagrass Posidonia oceanica,an ecosystem engineer thriving from the surface down to 40 m depth,to uncover how it maintains efficient photosynthesis across this gradient.Combining spectroscopy with pigment and blue native-PAGE analysis,we show that P.oceanica maintains a high but stable photosystem I(PSI)/PSII ratio and constant antenna size at all depths,in conjunction with a high abundance of light-harvesting complex II(LHCII).Electron microscopy observation indicated that adjustment of photosynthetic efficiency along the depth gradient is primarily achieved through structural remodeling of thylakoid architecture,rather than major changes in photosystem composition.We also identify a previously undescribed large PSI supercomplex(L-PSI-LHCII)that binds an additional Lhca1-Lhca4 dimer and a phosphorylated LHCII trimer.This complex,expressed at all tested depths,is enriched in chlorophyll b,lacks the far-red-absorbing chlorophylls(red forms)typical of land plants,and exhibits distinct energy-transfer dynamics optimized for blue-light harvesting.The presence of similar PSI supercomplex in other marine seagrasses,such as Zostera marina,suggests a conserved strategy among deep-growing species.Collectively,these results reveal how seagrasses combine structural adaptation at the level of PSI with thylakoid architecture reorganization to sustain efficient photosynthesis and long-term carbon fixation under blue-dominated marine light. 展开更多
关键词 eco-photophysiology Posidonia oceanica thylakoid architecture photosystem I LHCII chlorophyll b
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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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湖北三峡井网丁家坪井水位动态变化特征和影响因素分析
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作者 翁骋 吕品姬 +2 位作者 蒋玲霞 涂先新 周晓成 《地震工程学报》 北大核心 2026年第2期427-436,共10页
丁家坪井隶属于长江三峡工程诱发地震地下水动态观测井网(三峡井网),观测数据稳定、可靠。研究该井的水位动态变化和影响因素对判断三峡库区的地震活动性尤为重要。文章采用多学科交叉的研究方法,包括水文地质调查、小波分析、小波相干... 丁家坪井隶属于长江三峡工程诱发地震地下水动态观测井网(三峡井网),观测数据稳定、可靠。研究该井的水位动态变化和影响因素对判断三峡库区的地震活动性尤为重要。文章采用多学科交叉的研究方法,包括水文地质调查、小波分析、小波相干分析以及水化学监测等综合技术手段,旨在揭示地下水变化特征及其相关的影响因素。结果表明:(1)对比井水位和降雨的连续小波功率谱发现,二者高能量周期域分布存在较多重合;小波相干谱表明二者在短期(0~3.8 d)和中长期(100~512 d)的相关性较好,而中短期(5~64 d)的相关性略差。(2)对比井水位和库水位连续小波功率谱发现,二者高能量周期域重合区域较少;小波相干谱表明,二者的相关性较差。(3)水化学分析认为,丁家坪井与周围地表水水化学类型一致,证明丁家坪井与地表水存在相同的物质来源;Na-K-Mg三角图中,各样品均落在未成熟水处,进一步表明各采样点均为浅层地下水,受地表水补给;氢氧同位素分析结果表明,所有样品(包括丁家坪井水)均靠近三峡秭归段大气降水线,说明各样品的井水来源主要为大气降水。研究分析认为,丁家坪井的水力来源主要为大气降水,受库区水和深部来源水补给较少。 展开更多
关键词 三峡井网 地下流体 水化学 小波相干分析
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高分遥感解译下的2025年定日M_(S)6.8地震房屋震害特征及量化评估
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作者 陈鹏 钟秀梅 +2 位作者 李晨 胡雪枫 王谦 《地震工程学报》 北大核心 2026年第2期366-375,共10页
2025年1月7日,西藏自治区日喀则市定日县发生M_(S)6.8地震,造成严重的房屋损毁与人员伤亡。为快速获取震害信息,基于高分二号(GF-2)卫星遥感影像,选取高烈度区(Ⅸ度、Ⅷ度和Ⅶ度)典型乡镇(长所乡、措果乡和曲洛乡)开展房屋震害解译,分... 2025年1月7日,西藏自治区日喀则市定日县发生M_(S)6.8地震,造成严重的房屋损毁与人员伤亡。为快速获取震害信息,基于高分二号(GF-2)卫星遥感影像,选取高烈度区(Ⅸ度、Ⅷ度和Ⅶ度)典型乡镇(长所乡、措果乡和曲洛乡)开展房屋震害解译,分析房屋震害特征及其影响因素,并基于解译结果构建房屋遥感震害指数与断层距的拟合关系,分析破坏比与地震烈度的关系。结果表明:3个乡1435栋房屋在地震作用下发生不同程度的损坏(完全倒塌、局部倒塌/破坏、基本完好),老旧砖木结构及密集自建房倒塌严重,新建房屋抗震性能显著优于老旧民居;随着烈度增加,建筑物完全倒塌和局部倒塌/破坏的占比显著升高,Ⅸ度区房屋倒塌占比最高(措果乡27.90%、长所乡26.20%);房屋震害指数与地震烈度呈正相关,措果、长所两乡Ⅸ度区的遥感震害指数分别为0.44和0.48,而曲洛乡Ⅷ度与Ⅶ度区的遥感震害指数分别降低至0.19和0.12;空间分布上,损毁房屋集中沿登么错断裂带展布,在靠近断裂处房屋破坏最为严重,远离断裂带处震害较轻。研究结果有助于提升震后灾情快速评估能力,为灾后应急响应和救援决策提供数据支撑。 展开更多
关键词 定日M_(S)6.8地震 高分遥感影像 遥感评估 房屋震害 断层距
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基于强震记录的场地液化触发时间识别新方法
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作者 闫倬闻 袁晓铭 +4 位作者 袁近远 李瑞山 吴晓阳 杨阳 刘汉龙 《岩土工程学报》 北大核心 2026年第4期835-844,共10页
地震下土体液化前后其力学性质会发生突变,引起的地表和结构破坏机制也将发生质变。因此,确定液化触发时间对于把握液化灾害的动力演变过程以及控制液化灾害具有重要意义。本研究提出了基于强震记录的场地液化触发时间识别的新方法。基... 地震下土体液化前后其力学性质会发生突变,引起的地表和结构破坏机制也将发生质变。因此,确定液化触发时间对于把握液化灾害的动力演变过程以及控制液化灾害具有重要意义。本研究提出了基于强震记录的场地液化触发时间识别的新方法。基于双层土理论模型,分析孔压发展与场地基本周期、地表加速度频率变化之间的关系,阐明了方法的基本原理;以时频分析技术和频率下降率参数量化加速度记录的时频特征,形成了方法的技术流程。采用全球11次地震中的24条实际液化场地强震记录以及数值模拟手段,对既有两种方法和本文新方法进行对比检验,结果表明了本文新方法的优势。新方法不仅精度更高,而且主控参数阈值来自于理论模型,独立于经验数据,更具一般性和普适性,克服了既有方法需要人为干预而他人难以复现以及依赖于实测记录等缺点,便于推广应用。 展开更多
关键词 场地液化 液化时间 时频分析 频率下降率
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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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基于热稳频激光器的激光干涉绝对重力仪长度基准误差溯源分析
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作者 李子路 吴琼 +2 位作者 张旸 牛永卓 汤一翔 《大地测量与地球动力学》 北大核心 2026年第4期467-472,共6页
激光干涉绝对重力仪以稳频激光波长作为精密长度基准,其基准源选择会直接影响测量结果的准确度和精度。针对碘饱和吸收稳频激光器与热稳频激光器的工程应用差异,重点分析热稳频激光器的波长精度和重复性问题。通过构建基于碘稳频激光基... 激光干涉绝对重力仪以稳频激光波长作为精密长度基准,其基准源选择会直接影响测量结果的准确度和精度。针对碘饱和吸收稳频激光器与热稳频激光器的工程应用差异,重点分析热稳频激光器的波长精度和重复性问题。通过构建基于碘稳频激光基准的拍频测量系统,实现了热稳频激光器波长精度和重复性的测量,对绝对重力测量最终结果相同的统计处理模型进行采样,量化被测激光器输出波长的重复性和精度。结果表明,被测热稳频激光器输出波长精度优于4×10^(-9)nm,重复性优于1.86×10^(-6)nm。即热稳频激光器在锁定过程中,波长精度引起的重力测量误差远小于1μGal,波长的重复性引起的绝对重力测量示值误差为2.79μGal,这对于观测精度为10μGal的绝对重力测量需求而言可以接受,为基于热稳频激光器的绝对重力仪器在野外环境下的工程化应用提供了完整的计量学依据。 展开更多
关键词 热稳频激光器 绝对重力仪 长度基准误差 绝对重力测量
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基于InSAR技术的海原断裂大水头跨断层场地异常核实与分析
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作者 刘艳慧 季灵运 +2 位作者 朱良玉 刘传金 张文婷 《大地测量与地球动力学》 北大核心 2026年第3期343-348,共6页
观测资料显示,海原断裂带大水头跨断层BM1-BM3支线于2023-11出现1.52 mm的逆断变化,2024-03-06再次出现1.71 mm的逆断突跳变化。为核实此次异常是否与构造运动有关,利用InSAR技术获取大水头跨断层场地区域地表形变的时间序列,从形变场... 观测资料显示,海原断裂带大水头跨断层BM1-BM3支线于2023-11出现1.52 mm的逆断变化,2024-03-06再次出现1.71 mm的逆断突跳变化。为核实此次异常是否与构造运动有关,利用InSAR技术获取大水头跨断层场地区域地表形变的时间序列,从形变场空间展布以及时间演化2个方面,分析跨断层形变异常的可能成因。结果表明:1)场地周围的煤矿开采区沉降明显,且沉降速率随时间变化较快,2023-01—2024-06的累积沉降量最大约23 cm,显著沉降范围最大约1 km^(2);2)水准点受矿区沉降影响显著,且随时间的推移均有不同程度的沉降,距离矿区越近沉降量级越大,速率越快;3)对比InSAR与水准观测结果,发现同时间段跨断层形变趋势和量级基本一致。综上,大水头跨断层水准形变异常极大可能是矿区沉降导致的。 展开更多
关键词 海原断裂 大水头 跨断层场地 INSAR 异常核实
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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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