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Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour H.Al-Hashim Abdelbaset s.El-sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation compris.s a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands.seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red sea, northwestern saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analys.s were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analys.s reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenes.s and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in sr and Ca levels and increase in Mg,Na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenes.s Geochemistry saudi Arabia

Contribution of glial cells to the neuroprotective effects triggered by repetitive magnetic stimulation:a s.stematic review

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Neural Regeneration Research 2024年第1期19卷 116-123页

作者： s.sana A.Ferreira Nuno Pinto Inês.serrenho Maria Vaz Pato Graça Baltazar Centro de Investigação em Ciências da saúde(CICs-UBI) Universidade da Beira InteriorCovilhãPortugal Faculdade de Ciências da saúde Universidade da Beira InteriorCovilhãPortugal GRUBI-s.stematic Reviews Group University of Beira InteriorCovilhãPortugal

Repetitive transcranial magnetic stimulation has been increasingly studied in different neurological diseas.s,and although most studies focus on its effects on neuronal cells,the contribution of nonneuronal cells to the improvement trigge red by repetitive transcranial magnetic stimulation in these diseas.s has been increasingly *** s.stematically review the effects of repetitive magnetic stimulation on non-neuronal cells two online *** of science and PubMed were searched fo r the effects of high-frequency-repetitive transcranial magnetic stimulation,low-frequencyrepetitive transcranial magnetic stimulation,intermittent theta-bu rst stimulation,continuous thetaburst stimulation,or repetitive magnetic stimulation on non-neuronal cells in models of disease and in unlesioned animals or cells.A total of 52 studies were *** protocol more frequently used was high-frequency-repetitive magnetic stimulation,and in models of disease,most studies report that high-frequency-repetitive magnetic stimulation led to a decrease in astrocyte and mic roglial reactivity,a decrease in the release of pro-inflammatory cyto kines,and an increase of oligodendrocyte *** trend towards decreased microglial and astrocyte reactivity as well as increased oligodendrocyte proliferation occurred with intermittent theta-burst stimulation and continuous theta-burst *** papers analyzed the low-frequency-repetitive transcranial magnetic stimulation protocol,and the parameters evaluated were restricted to the study of astrocyte reactivity and release of pro-inflammatory cytokines,repo rting the absence of effects on these paramete *** what concerns the use of magnetic stimulation in unlesioned animals or cells,most articles on all four types of stimulation reported a lack of *** is also important to point out that the studies were developed mostly in male rodents,not evaluating possible diffe rential effects of repetitive transcranial magneti

关键词： astrocyte glia high-frequency repetitive magnetic stimulation inflammation low-frequency repetitive magnetic stimulation microglia neurologic disorders oligodendrocyte repetitive magnetic stimulation theta-burst stimulation

切尔诺贝利事故辐射受照人员淋巴细胞核的形态变化

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中国辐射卫生 2009年第2期18卷 129-131页

作者：李雨 Kravtsov V.Yu Aleksanin s.s 上海第二军医大学海医系放射医学教研室上海200433 俄罗斯急救与放射医学中心

目的观察受照射的切尔诺贝利事故清理工作者外周血淋巴细胞核特殊形态变化。方法选取切尔诺贝利事故清理工作者作为试验组,采用常规方法取指尖外周血制备涂片,空气干燥,对氨基苯甲酸混合,Giemsa法染色,光镜下计数每人500个细胞样本,观... 详细信息

目的观察受照射的切尔诺贝利事故清理工作者外周血淋巴细胞核特殊形态变化。方法选取切尔诺贝利事故清理工作者作为试验组,采用常规方法取指尖外周血制备涂片,空气干燥,对氨基苯甲酸混合,Giemsa法染色,光镜下计数每人500个细胞样本,观察记录不同特殊形态核发生率,进行统计学处理。结果大多数受照射对象都出现较多带有尾状突起的淋巴细胞。根据这些核上突起的尾状物形态特征将其分为16种类型并分别记录了每种尾状突起细胞的发生率并进行分布率分析。结论受照射淋巴细胞核尾状突起变化可能是一种有意义的受照射标记物,对于更加详尽获取辐射生物效应信息,回顾性研究辐射剂量效应可能具有理论和实践价值。

关键词：切尔诺贝利核事故辐射淋巴细胞

Effect of Eu^(3+),Bi^(3+),and Li^(+) doping on luminescent property of GdNbO_(4)

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Journal of Rare Earths 2024年第1期42卷 66-75,I0003页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil UniversitySeoul06978Republic of Korea

We investigated the emission properties of Eu^(3+)-doped GdNbO_(4)-based oxide phosphors,aiming at improving the Eu^(3+)emission by codoping of Bi^(3+)and Li^(+).Eu^(3+)singly doped,Eu^(3+)and Bi^(3+)doubly doped,and Eu^(3+),Bi^(3+),and Li^(+)triply doped GdNbO_(4)were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu^(3+)in the singly doped samples are significantly improved by the codoping of Bi^(3+),mainly due to the energy transfer from Bi^(3+)to Eu^(3+).The additional codoping of Li^(+)is found to increase the Eu^(3+)emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analys.s of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu^(3+)in GdNbO_(4)does not change significantly with the codoping of Bi^(3+)and Li^(+).Our results indicate that Li^(+)doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO_(4)phosphors.

关键词： Eu^(3+) GdNbO_(4) Codoping of Li^(+) Photoluminescence sensitizer Rare earths

Hypoxic and temporal variation in the endocrine disrupting toxicity of perfluorobutanesulfonate in marine medaka(Oryzias melastigma)

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Journal of Environmental sciences 2024年第2期136卷 279-291页

作者： Baili sun Jing Li Yachen Bai Xiangzhen Zhou Paul K.s.Lam Lianguo Chen state Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China University of Chinese Academy of sciences Beijing 100049China Office of the President Hong Kong Metropolitan University30 Good Shepherd StreetKowloonHong Kong SARChina

Perfluorobutanesulfonate(PFBs)is an emerging pollutant capable of potently disrupting the sex and thyroid endocrine s.stems of ***,the hypoxic and temporal variation in PFBs endocrine disrupting toxicity remain largely *** the present study,adult marine medaka were exposed to environmentally realistic concentrations of PFBs(0 and 10μg/L)under normoxia or hypoxia conditions for 7 days,aiming to explore the interactive behavior between PFBs and *** addition,PFBs.singular exposure was extended till 21days under normoxia to elucidate the time-course progression in PFBs *** results.showed that hypoxia inhibited the growth and caused the s.spension of egg spawn regardless of PFBs *** regard to the sex endocrine s.stem,7-day PFBs exposure led to an acute stimulation of transcriptional profiles in females,which,subsequently,recovered after the 21-day *** potency of hypoxia to disturb the sex hormones was much stronger than PFBs.A remarkable increase in estradiol concentration was noted in medaka blood after hypoxia *** in sex endocrinology of coexposed fish were largely determined by hypoxia,which drove the formation of an estrogenic *** further enhanced the endocrine disrupting effects of ***,the hepatic synthes.s of vitellogenin and choriogenin,two commonly used sensitive biomarkers of estrogenic activity,failed to initiate in response to the estrogen *** to sex endocrine s.stem,disturbances in thyroidal axis by PFBs or hypoxia were relatively ***,the present findings will advance our toxicological understanding about PFBs pollutant under the interference of hypoxia.

关键词： Perfluorobutanesulfonate(PFBs) Aquatic hypoxia Temporal toxicity Combined exposure Endocrine disruption Marine medaka

Verdier quotients of homotopy categories of rings and Gorenstein-projective precovers

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science China Mathematics 2024年

作者： Manuel Cortés-Izurdiaga Departamento de Matemática Aplicada Universidad de Málaga

Let R be a ring, Proj be the class of all the projective right R-modules, K be the full subcategory of the homotopy category K(Proj) whose class of objects cons.sts of all the totally acyclic complexes, and MorK be the class of all the morphis.s in K(Proj) whose cones belong to K. We prove that if K(Proj) has enough MorK-injective objects, then the Verdier quotient K(Proj)/K has.small Hom-sets, and this last condition implies the existence of Gorenstein-projective precovers in Mod-R and of totally acyclic precovers in C(Mod-R).

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Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-ANN approach

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Frontiers of structural and Civil Engineering 2024年第3期18卷 428-443页

作者： Hedye JALALI Reza YEGANEH KHAKsAR Danial MOHAMMADZADEH s. Nader KARBALLAEEZADEH Amir H.GANDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this.study,the complex behavior of soil and a buried pipeline s.stem subjected to a normal fault is analyzed by using an artificial neural network(ANN)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the ANN includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on bias.s and weights of the ANN *** results.show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

Review of tribological properties of nanoparticle-based lubricants and their hybrids and composites

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Friction 2024年第4期12卷 569-590页

作者： Ye Zar Ni HTWE Aws.s.AL-JANABI Yasmin WADZER Hussin MAMAT Ku NOORYAsMIN school of Materials&Mineral Resources Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia school of Aerospace Engineering Universiti Sains Malaysia(Engineering Campus)Nibong Tebal 14300Malaysia Universiti sains Malaysia

Due to their encouraging results,nanolubricants have been revolutionary in the field of *** degree,to which the new material may improve the tribology,energy savings,and durability,is a crucial consideration for any new additive to a conventional *** results of the earlier research on carbon,metal,metal oxide,and their composites and hybrid nanolubricants as well as their effects on tribology,are summarized in this review *** most popular measuring methodologies,the tribology results for lubricants with an oil base,biodegradable base,and a water base,as well as the reasons that explain these tribological advancements,are all included in this ***,prospects for more study in this area are emphasized.

关键词： nanolubricants tribology carbon metal metal oxide hybrid

非动脉炎性前部缺血性视神经病变的视野异常:初诊的视野表现及患病率

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世界核心医学期刊文摘(眼科学分册) 2006年第3期 23-24页

作者： Hayreh s.s Zimmerman B. 陈立军 Departmentof Ophthalmology and Visual sciences UniversityHospitals and Clinics 200 Hawkins Dr Iowa City IA52242-1091 United StatesDr.

Objective: To evaluate the pattern of various types of visual field defects and their prevalence at initial examination of nonarteritic anterior ischemic optic neuropathy (NA-AION).Methods: The data were compiled from 312 consecutive eyes (in 265 patients)that fulfilled our inclusion and exclusion criteria. A comprehensive ophthalmic evaluation was performed, includingre cording of visual acuity, visual fields with a Goldmann perimeter (using I-2e, I-4e, and V-4e targets regularly), and intraocular pressure; slitlamp examination of the anterior segment;ophthalmoscopy; color fundus photography; and in acute cas.s, fluorescein fundus angiography. The visual field defects were divided into 2 groups: (1) general field defects and (2)-various types of scotoma in the central 30°. The prevalence of various types of visual field defects was estimated for I-2e, I-4e, and V-4e isopters by dividing the total number of eyes with thedefect by the total number of eyes that could see that particulartarget. Exact 95%confidence limits for the prevalence were computed. Results: Of the 265 patients, 169 (63.7%) were male and the mean±sD patient age was 55.0±9.1 years. The median interval between the first visual field test and the onset of NA-AION was 2 weeks. Of the 312 eyes, the I-2e target was.seen by 75.3%, the I-4e target by 90.7%, and the V-4e targetby 100%. Overall prevalence of general visual field defects was 83.4%with I-2e, 78.8%with I-4e, and 68.9%with V-4e,whereas the prevalence of scotoma(s) within the central 30°was 55.3%, 49.5%, and 36.2%, respect ively. Central scotoma was.seen in 48.5%with I-2e, 43.8%with I-4e, and 29.2%with V-4e. A detailed prevalence of various types of visualfield defects is given. Relative inferior altitudinal defect was most common (34.9%with I-2e and 22.3%with I-4e), but the absolute inferior altitudinal defect was.seen in only 8.0%. Bycontrast, absolute inferior nasal sector visual loss was the most common defect detected in NA-AION (22.4%), bu

关键词：非动脉炎性前部缺血性视神经病变视野缺损患病率