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Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration
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作者 Yun Li Junfang Wu 《Neural Regeneration Research》 SCIE CAS 2025年第2期483-484,共2页
Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability worldwide.Advances in assistive technology,rehabilitative interventions,and... Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability worldwide.Advances in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth decade.These survival changes have led neurotrauma researchers to examine how SCI interacts with brain aging.Public health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications. 展开更多
关键词 alterations INFLAMMATION INJURY
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Genetic and epigenetic alterations associated with gestational diabetes mellitus and adverse neonatal outcomes
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作者 Amreen Shamsad Tanu Gautam +1 位作者 Renu Singh Monisha Banerjee 《World Journal of Clinical Pediatrics》 2025年第1期6-20,共15页
Gestational diabetes mellitus(GDM)is a metabolic disorder,recognised during 24-28 weeks of pregnancy.GDM is linked with adverse newborn outcomes such as macrosomia,premature delivery,metabolic disorder,cardiovascular,... Gestational diabetes mellitus(GDM)is a metabolic disorder,recognised during 24-28 weeks of pregnancy.GDM is linked with adverse newborn outcomes such as macrosomia,premature delivery,metabolic disorder,cardiovascular,and neurological disorders.Recent investigations have focused on the correlation of genetic factors such asβ-cell function and insulin secretary genes(transcription factor 7 like 2,potassium voltage-gated channel subfamily q member 1,adipo-nectin etc.)on maternal metabolism during gestation leading to GDM.Epigenetic alterations like DNA methylation,histone modification,and miRNA expression can influence gene expression and play a dominant role in feto-maternal meta-bolic pathways.Interactions between genes and environment,resulting in differ-ential gene expression patterns may lead to GDM.Researchers suggested that GDM women are more susceptible to insulin resistance,which alters intrauterine surroundings,resulting hyperglycemia and hyperinsulinemia.Epigenetic modi-fications in genes affecting neuroendocrine activities,and metabolism,increase the risk of obesity and type 2 diabetes in offspring.There is currently no treatment or effective preventive method for GDM,since the molecular processes of insulin resistance are not well understood.The present review was undertaken to un-derstand the pathophysiology of GDM and its effects on adverse neonatal out-comes.In addition,the study of genetic and epigenetic alterations will provide lead to researchers in the search for predictive molecular biomarkers. 展开更多
关键词 Gene expression Gestational diabetes mellitus Feto-maternal outcome Epigenetic alteration Molecular biomarkers
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Hydrothermal alteration of the surface volcanic rocks at the Acoculco geothermal field,Mexico:a multi-parametric approach
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作者 America Yosiris García-Soto Kailasa Pandarinath +1 位作者 ESantoyo Eduardo Gonzalez-Partida 《Acta Geochimica》 EI CAS CSCD 2024年第6期1037-1053,共17页
The studies on hydrothermal alteration-induced eff ects in surface and subsurface rocks provide useful information in the characterization and exploitation of a geothermal reservoir.Generally,these studies are based o... The studies on hydrothermal alteration-induced eff ects in surface and subsurface rocks provide useful information in the characterization and exploitation of a geothermal reservoir.Generally,these studies are based on traditional,and reliable methods like petrography(primary and secondary minerals,and grade of alteration),and geochemistry(mobility of elements,changes in mass and concentration of elements,and fluid inclusions).Recently,apart from these established methods,some methods based on the geochemical(Chemical Index of Alteration,CIA;Weathering Index of Parkar,WIP;Loss on Ignition,LOI;and Sulfur,S)and rock magnetic properties(magnetic susceptibility,χlf;and percentage frequency-dependent susceptibility,χfd%)are also being applied in the identification of whether a rock is an altered or a fresh one.The Acoculco Geothermal Field(AGF),Mexico,is characterized by high temperature and very low permeability,and it is considered a promissory Enhanced Geothermal System.The following changes are observed in the rocks as a result of an increase in hydrothermal alteration:(1)an increase in CIA,LOI,and S values,and a decrease in WIP;(2)an increase in quartz and quartz polymorph minerals(silicification),and clay minerals(argillization);and(3)decrease inχlf values.At AGF,the most altered surface acid rocks are characterized by entirely quartz and its polymorphs,and clay minerals.The present study also indicates the applicability of the binary plots of major elements(felsic vs mafic component)and rock magnetic parameters(χlf vs.χfd%).The rock withχfd%value of 2-10 andχlf value<0.5×10^(-6)m^(3) kg^(-1)indicate the presence of single domain and stable single domain grains,which in turn suggests that it is an altered rock.These methods are simple to apply,rapid,reliable,and have the potential to become eff ective tools for the identifi cation of hydrothermally altered rocks during the initial stage of geothermal exploration. 展开更多
关键词 Geothermal fields Hydrothermal alteration Surface rocks Magnetic susceptibility alteration indices
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A Blade Altering Toolbox for Automating Rotor Design Optimization
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作者 Akiva Wernick Jen-Ping Chen 《Communications on Applied Mathematics and Computation》 EI 2024年第1期688-704,共17页
The Blade Altering Toolbox(BAT)described in this paper is a tool designed for fast reconstruction of an altered blade geometry for design optimization purposes.The BAT algorithm is capable of twisting a given rotor’s... The Blade Altering Toolbox(BAT)described in this paper is a tool designed for fast reconstruction of an altered blade geometry for design optimization purposes.The BAT algorithm is capable of twisting a given rotor’s angle of attack and stretching the chord length along the span of the rotor.Several test cases were run using the BAT’s algorithm.The BAT code’s twisting,stretching,and mesh reconstruction capabilities proved to be able to handle reasonably large geometric alterations to a provided input rotor geometry.The test examples showed that the toolbox’s algorithm could handle any stretching of the blade’s chord as long as the blade remained within the original bounds of the unaltered mesh.The algorithm appears to fail when the net twist angle applied the geometry exceeds approximately 30 degrees,however this limitation is dependent on the initial geometry and other input parameters.Overall,the algorithm is a very powerful tool for automating a design optimization procedure. 展开更多
关键词 Mesh reconstruction Mesh alteration Rotor alteration Design optimization
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Risk stratification for radioactive iodine refractoriness using molecular alterations in distant metastatic differentiated thyroid cancer 被引量:3
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作者 Zhuanzhuan Mu Xin Zhang +9 位作者 Dongquan Liang Jugao Fang Ge Chen Wenting Guo Di Sun Yuqing Sun Zhentian Kai Lisha Huang Jun Liang Yansong Lin 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第1期25-35,共11页
Objective: Patients with radioactive iodine-refractory differentiated thyroid cancer(RAIR-DTC) are often diagnosed with delay and constrained to limited treatment options. The correlation between RAI refractoriness an... Objective: Patients with radioactive iodine-refractory differentiated thyroid cancer(RAIR-DTC) are often diagnosed with delay and constrained to limited treatment options. The correlation between RAI refractoriness and the underlying genetic characteristics has not been extensively studied.Methods: Adult patients with distant metastatic DTC were enrolled and assigned to undergo next-generation sequencing of a customized 26-gene panel(Thyro Lead). Patients were classified into RAIR-DTC or non-RAIR groups to determine the differences in clinicopathological and molecular characteristics. Molecular risk stratification(MRS) was constructed based on the association between molecular alterations identified and RAI refractoriness, and the results were classified as high, intermediate or low MRS.Results: A total of 220 patients with distant metastases were included, 63.2% of whom were identified as RAIRDTC. Genetic alterations were identified in 90% of all the patients, with BRAF(59.7% vs. 17.3%), TERT promoter(43.9% vs. 7.4%), and TP53 mutations(11.5% vs. 3.7%) being more prevalent in the RAIR-DTC group than in the non-RAIR group, except for RET fusions(15.8% vs. 39.5%), which had the opposite pattern. BRAF and TERT promoter are independent predictors of RAIR-DTC, accounting for 67.6% of patients with RAIR-DTC. MRS was strongly associated with RAI refractoriness(P<0.001), with an odds ratio(OR) of high to low MRS of 7.52 [95%confidence interval(95% CI), 3.96-14.28;P<0.001] and an OR of intermediate to low MRS of 3.20(95% CI,1.01-10.14;P=0.041).Conclusions: Molecular alterations were associated with RAI refractoriness, with BRAF and TERT promoter mutations being the predominant contributors, followed by TP53 and DICER1 mutations. MRS might serve as a valuable tool for both prognosticating clinical outcomes and directing precision-based therapeutic interventions. 展开更多
关键词 Differentiated thyroid cancer distant metastases genetic alterations RAI refractoriness molecular risk stratification
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Genomic alterations in oral multiple primary cancers
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作者 Wen Wang Qian Wang +7 位作者 Shiying Sun Pengfei Zhang Yuyu Li Weimin Lin Qiwen Li Xiao Zhang Zhe Ma Haiyan Lu 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期145-153,共9页
Oral squamous cell carcinoma (OSCC) is the predominant type of oral cancer, while some patients may develop oral multiple primary cancers (MPCs) with unclear etiology. This study aimed to investigate the clinicopathol... Oral squamous cell carcinoma (OSCC) is the predominant type of oral cancer, while some patients may develop oral multiple primary cancers (MPCs) with unclear etiology. This study aimed to investigate the clinicopathological characteristics and genomic alterations of oral MPCs. Clinicopathological data from patients with oral single primary carcinoma (SPC, n=202) and oral MPCs (n=34) were collected and compared. Copy number alteration (CNA) analysis was conducted to identify chromosomal-instability differences among oral MPCs, recurrent OSCC cases, and OSCC patients with lymph node metastasis. Whole-exome sequencing was employed to identify potential unique gene mutations in oral MPCs patients. Additionally, CNA and phylogenetic tree analyses were used to gain preliminary insights into the molecular characteristics of different primary tumors within individual patients. Our findings revealed that, in contrast to oral SPC, females predominated the oral MPCs (70.59%), while smoking and alcohol use were not frequent in MPCs.Moreover, long-term survival outcomes were poorer in oral MPCs. From a CNA perspective, no significant differences were observed between oral MPCs patients and those with recurrence and lymph node metastasis. In addition to commonly mutated genes such as CASP8, TP53 and MUC16, in oral MPCs we also detected relatively rare mutations, such as HS3ST6 and RFPL4A. Furthermore, this study also demonstrated that most MPCs patients exhibited similarities in certain genomic regions within individuals, and distinct differences of the similarity degree were observed between synchronous and metachronous oral MPCs. 展开更多
关键词 alterations METASTASIS ORAL
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Identifying Comprehensive Genomic Alterations and Potential Neoantigens for Cervical Cancer Immunotherapy in a Cohort of Chinese Squamous Cell Carcinoma of the Cervix
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作者 Meng Wu Jialu Zhou +1 位作者 Zhe Zhang Yuanguang Meng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第6期565-580,共16页
Objective Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma(CSCC).Methods Whole-exome sequencing was ... Objective Genomic alterations and potential neoantigens for cervical cancer immunotherapy were identified in a cohort of Chinese patients with cervical squamous cell carcinoma(CSCC).Methods Whole-exome sequencing was used to identify genomic alterations and potential neoantigens for CSCC immunotherapy.RNA Sequencing was performed to analyze neoantigen expression.Results Systematic bioinformatics analysis showed that C>T/G>A transitions/transversions were dominant in CSCCs.Missense mutations were the most frequent types of somatic mutation in the coding sequence regions.Mutational signature analysis detected signature 2,signature 6,and signature 7 in CSCC samples.PIK3CA,FBXW7,and BICRA were identified as potential driver genes,with BICRA as a newly reported gene.Genomic variation profiling identified 4,960 potential neoantigens,of which 114 were listed in two neoantigen-related databases.Conclusion The present findings contribute to our understanding of the genomic characteristics of CSCC and provide a foundation for the development of new biotechnology methods for individualized immunotherapy in CSCC. 展开更多
关键词 Cervical squamous cell carcinoma Genome alteration Neoantigens IMMUNOTHERAPY
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Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea
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作者 Xin-Ru Wang Bao-Zhi Pan +2 位作者 Yu-Hang Guo Qing-Hui Wang Yao Guan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期206-220,共15页
There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.Howe... There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir evaluation.However,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably difficult.At the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous formations.To overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous rocks.Specifically,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric model.Then we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and porosity.However,it is always difficult to determine the elemental eigenvalues of different minerals in inversion.This paper uses multiple linear regression methods to solve this problem.Finally,an integrated inversion technique for altered igneous formations was developed.The results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray diffraction.The results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formations. 展开更多
关键词 Joint inversion altered igneous rock Element correction method Lithology identification Multi mineral volume model
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Age-Related Alterations in Peripheral Immune Landscape with Magnified Impact on Post-Stroke Brain
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作者 Jianan Lu Huaming Li +10 位作者 Guoqiang Zhangi Fan Yangi Xiaotao Zhangi An Pingi Zhouhan Xui Yichen Gui Rui Wangi Dan Yingi Jianjian Liui Jianmin Zhangi Ligen Shi 《Research》 SCIE EI CSCD 2024年第3期51-69,共19页
Immunosenescence refers to the multifaceted and profound alterations in the immune system brought about by aging,exerting complex influences on the pathophysiological processes of diseases that manifest upon it.Using ... Immunosenescence refers to the multifaceted and profound alterations in the immune system brought about by aging,exerting complex influences on the pathophysiological processes of diseases that manifest upon it.Using a combination of single-cell RNA sequencing,cytometry by time of flight,and various immunological assays,we investigated the characteristics of immunosenescence in the peripheral blood of aged mice and its impact on the cerebral immune environment after ischemic stroke.Our results revealed some features of immunosenescence.We observed an increase in neutrophil counts,concurrent with accelerated neutrophil aging,characterized by altered expression of aging-associated markers like CD62L and consequential changes in neutrophil-mediated immune functions.Monocytes/macrophages in aged mice exhibited enhanced antigen-presentation capabilities.T cell profiles shifted from naive to effector or memory states,with a specific rise in T helper 1 cells and T helper 17 cells subpopulations and increased regulatory T cell activation in CD4 T cells.Furthermore,regulatory CD8 T cells marked by Klra decreased with aging,while a subpopulation of exhausted-like CD8 T cells expanded,retaining potent immunostimulatory and proinflammatory functions.Critically,these inherent disparities not only persisted but were further amplified within the ischemic hemispheres following stroke.In summary,our comprehensive insights into the key attributes of peripheral immunosenescence provide a vital theoretical foundation for understanding not only ischemic strokes but also other age-associated diseases. 展开更多
关键词 alterations retaining IMPACT
原文传递
Clinicopathological alterations in wild mammals from the reservoir system of Trypanosoma cruzi:a scoping review
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作者 Ricardo Sanchez Pérez JoséManuel Aranda-Coello +1 位作者 JoséAntonio De Fuentes Vicente Oscar Rico Chavez 《Animal Diseases》 CAS 2024年第1期48-58,共11页
Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as&... Trypanosoma cruzi is the etiologic agent of Chagas disease.This flagellated protozoan is transmitted to humans as well as different species of domestic and wild animals via vectors from the Reduviidae family(known as"kissing bugs").Despite the fact that hundreds of species of wild mammals are part of the reservoir system,the morphologi-cal changes and clinical manifestations resulting from the pathogenesis of the infection have been largely neglected.The aim of this review is to systematically compile the available information regarding clinicopathological altera-tions in wild mammals due to natural infection by T.cruzi.Information was obtained from six online bibliographic data search platforms,resulting in the identification of 29 publications that met the inclusion criteria.Mortality was the most common clinical manifestation,cardiac damage was the main finding at necropsy,and lymphoplas-macytic inflammation was the most frequent microscopic injury.Thus,regardless of its role as a reservoir,T.cruzi has the potential to affect the health status of wild mammals,a situation that highlights the need for further research to analyze,measure,and compare its effects at both the individual and population levels. 展开更多
关键词 Trypanosoma cruzi Chagas disease American trypanosomiasis Clinicopathological alterations Natural infection Wild mammals
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Novel cyber-physical collaborative detection and localization method against dynamic load altering attacks in smart energy grids
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作者 Xinyu Wang Xiangjie Wang +2 位作者 Xiaoyuan Luo Xinping Guan Shuzheng Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期362-376,共15页
Owing to the integration of energy digitization and artificial intelligence technology,smart energy grids can realize the stable,efficient and clean operation of power systems.However,the emergence of cyber-physical a... Owing to the integration of energy digitization and artificial intelligence technology,smart energy grids can realize the stable,efficient and clean operation of power systems.However,the emergence of cyber-physical attacks,such as dynamic load-altering attacks(DLAAs)has introduced great challenges to the security of smart energy grids.Thus,this study developed a novel cyber-physical collaborative security framework for DLAAs in smart energy grids.The proposed framework integrates attack prediction in the cyber layer with the detection and localization of attacks in the physical layer.First,a data-driven method was proposed to predict the DLAA sequence in the cyber layer.By designing a double radial basis function network,the influence of disturbances on attack prediction can be eliminated.Based on the prediction results,an unknown input observer-based detection and localization method was further developed for the physical layer.In addition,an adaptive threshold was designed to replace the traditional precomputed threshold and improve the detection performance of the DLAAs.Consequently,through the collaborative work of the cyber-physics layer,injected DLAAs were effectively detected and located.Compared with existing methodologies,the simulation results on IEEE 14-bus and 118-bus power systems verified the superiority of the proposed cyber-physical collaborative detection and localization against DLAAs. 展开更多
关键词 Smart energy grids Cyber-physical system Dynamic load altering attacks Attack prediction Detection and localization
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Research on the Application of Electromagnetic Method in the Exploration of Altered Rock-type Gold Deposits in the East Kunlun Metallogenic Belt
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作者 DONG Ji’en ZHANG Huiqing +4 位作者 WANG Peng LI Hua YE Gaofeng YU Xiaoliang LI Jie 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第S01期18-21,共4页
Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,20... Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,2018).It is an important part of the Central Orogenic Belt(Xiong et al.,2023).It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al.,2023)and an essential potential base for mineral resources in China.Wulonggou and Gouli gold mines have been discovered successively,earning the reputation of the"Golden Belt of Qinghai Province"(Feng et al.,2004;He et al.,2023). 展开更多
关键词 electromagnetic method altered rock-type gold deposits Mailong mining area East Kunlun metallogenic belt
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Bilateral meibomian gland morphological alterations in unilateral herpes simplex keratitis based on artificial intelligence analysis
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作者 Xin-Xin Yu Xue-Wen Chen +1 位作者 Qi Dai Shuang-Qing Wu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第12期2153-2157,共5页
AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study... AIM:To explore whether unilateral herpes simplex keratitis(HSK)can cause morphological changes of bilateral meibomian glands(MGs)based on artificial intelligence(AI)analytical system.METHODS:In the retrospective study,29 patients with unilateral HSK and 29 participants matched in terms of age and sex were included as control group.Meibographic images of the upper eyelid using Keratograph 5M and assessed ocular surface parameters including tear meniscus height and tear break-up time.MG density and vagueness values were automatically analyzed and calculated using an AI analytical system.We compared the differences between the affected and the contralateral unaffected eyes in HSK patients,and the normal control eyes.We employed either the paired t-test or the Wilcoxon signed-rank test to compare significant difference between the affected and unaffected eyes in HSK patients or between the HSK group and control group.RESULTS:The MG density was 0.19±0.09 in the HSKaffected eye and 0.18±0.07 in contralateral unaffected eye,which had no significant difference(P=0.616).The MG density between the affected eye with HSK and the normal control group was statistically significant(P=0.028).There was a significant difference in MG density between the contralateral unaffected eye and the normal control group(P=0.012).However,no significant difference in vagueness value was observed between the eye with HSK and the control group or between HSK eye and contralateral eye.CONCLUSION:The MG density between the HSKaffected eye and the contralateral unaffected eye don’t significantly differ,whereas there is a significant decrease in the HSK group compared to that of the normal participants.Unilateral HSV keratitis may suffer from bilateral changes of MG morphology indicating bilateral dry eye.Therefore,the fellow eye of patients with unilateral HSK should be considered a potential case of MG dysfunction,necessitating early treatment for bilateral dry eye in the clinic. 展开更多
关键词 herpes simplex keratitis artificial intelligence meibomian gland morphology bilateral alterations
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Application of Remote Sensing and GIS in Mineral Alteration Mapping and Lineament Extraction Case of Oudiane Elkharoub (Requibat Shield, Northern of Mauritania)
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作者 Ould Mahmoud Hdeid Yousra Morsli +6 位作者 Mohamed Raji Zouhir Baroudi Malika Adjour Khaled Cheikh Nebagha Zein El Arby Vetah Mohamed El Moktar Isselmou Brahim Vall 《Open Journal of Geology》 CAS 2024年第9期823-854,共32页
The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation tech... The integration of remotely sensed data allowed the successful characterization of the mineral alteration zones of the Oudiane Elkharoub area in the Northeastern part of Reguibat Shield using image transformation techniques. As both chemical and geochemical analyses showed significant Au, Ag, Cu, Pb, Mn, Cr, Ni, Th and Y anomalies, it’s very interesting to apply the remote sensing and GIS in mineral resources mapping. The remote sensing is a direct adjunct to the field, lithologic and structural mapping, and more recently, GIS has played an important role in the study of mineralization areas. The integration of several evidential maps highlighted the plausible areas with high concentrations of chlorite, epidote, kaolinite, calcite, alunite, hematite, illite and sulfur among other key mineral alterations that reflect the intensity of hydrothermal effects and the probable sites of ore bodies. The methodological approach integrates geological information acquired from Aster and Landsat 8 OLI/TIRS (Operational Land Imager/Thermal InfraRed Sensor) images and a multi-criteria GIS analysis. The superimposition of various lineament and hydrothermal alteration maps and the consideration of precious and base metal indicators allowed the zoning of sites likely to contain mineral concentrations. Remote sensing becomes an important tool for locating mineral deposits in its own right, when the primary and secondary processes of mineralization result in the formation of spectral anomalies. Reconnaissance lithological mapping is usually the first step of mineral resource mapping. This is complimented with structural mapping, as mineral deposits usually occur along or adjacent to geologic structures, and alteration mapping, as mineral deposits are commonly associated with hydrothermal alteration of the surrounding rocks. Ground truthing and laboratory studies including XRD analysis were utilized to verify the results. 展开更多
关键词 Remote Sensing GIS ASTER Landsat 8 (OLI/TIRS) Structure Mineralization alterATION MINERAL LINEAMENT Reguibat Shield Oudiane Elkharoub
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Petrology and association of rare earth elements in magmatically altered high-ash coal of Indian origin
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作者 Riya Banerjee Saswati Chakladar +2 位作者 Alok Kumar Shyamal Kumar Chattopadhyay Sanchita Chakravarty 《International Journal of Coal Science & Technology》 CSCD 2024年第4期171-186,共16页
The extraction of valuables from waste has gained momentum.Thermal infuence alters both the organic and inorganic components of coal.Insufficient knowledge on the association of rare earth elements(REEs)with the paren... The extraction of valuables from waste has gained momentum.Thermal infuence alters both the organic and inorganic components of coal.Insufficient knowledge on the association of rare earth elements(REEs)with the parent matrix of thermally altered high-ash coals(63%ash)limits the potential for such coals being utilized for isolation of valuables.In this study,we analyzed the distribution and occurrence modes of REEs within a magmatically altered high-ash coal via nine-step sequential extraction,combining Tessier and BCR methods.The total concentration of REEs in the coal sample,on whole coal basis,was found to be 820 ppm,which is significantly higher than the world average.Major mineral oxides were deduced to be those of Si,Fe,Al,Ca,Mg,and Ti.Sequential extraction confirmed that about 66%of HREE and 25%of LREE were included in the residual fraction.LREEs were concluded to be primarily in ionic form,whereas HREEs were speculated to be associated with the TiO_(2) phase.XRD analyses showed that thermal alteration affected the dolomite phase specifically,which selectively got removed where carbonate-bound elements were assessed.Petrographic analysis supported the magmatic influence and demonstrated the presence of mosaic structures and pores containing unfused vitrinite,with a reflectance value of 3.6.To summarize,the present study pertaining to delineation of association of valuables in high-ash heat-altered coals from an Eastern coalfeld in India can potentially open up new avenues for utilizing such coals,which are otherwiseconsidered waste. 展开更多
关键词 Heat altered coal ASSOCIATION Petrography-Sequential leaching XRF XRD
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Hydrothermal Alteration Associated with the Kiaka World-Class Gold Deposit (Burkina Faso, West Africa)
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作者 Benjamin Sawadogo Gounwendmanaghré Hubert Zongo +5 位作者 Wilédio Marc-Emile Bonzi Kalidou Traore Sâga Sawadogo Ousseni Yameogo Ousmane Bamba Guy Franceschi 《Open Journal of Geology》 2024年第12期989-1015,共27页
This paper aims to show the relationships between hydrothermal alteration, deformation and gold mineralization in the main area of the Kiaka deposit. The Kiaka gold deposit is located in the South-central of Burkina F... This paper aims to show the relationships between hydrothermal alteration, deformation and gold mineralization in the main area of the Kiaka deposit. The Kiaka gold deposit is located in the South-central of Burkina Faso in the Tenkodogo volcano-sedimentary belt. Mineralization is primarily hosted by amphibolite, mylonitized quartz microdiorite and meta-sediment. The combination of petrographic, metallographic and geochemical analysis along with structural deformation of the ore body allowed us to distinguish the three main stages of hydrothermal alteration in the Kiaka gold deposit. (i) The first stage is characterized by ductile deformation which induces potassic- and LILE-rich alteration with crystallization of disseminated pyrrhotite. (ii) The second stage corresponds to chloritization and is associated with a brittle-ductile deformation and retrograde metamorphism. A second generation of disseminated pyrrhotite and a few pyrite and chalcopyrite crystallized during this event. Pyrrhotite also fills veins. (iii) The third alteration stage is characterized by a significant carbonation and concurrent with a brittle deformation. It is accompanied locally by a high-grade gold mineralization (up to 29 g/t). 展开更多
关键词 Gold Deposit Hydrothermal alteration DEFORMATION GEOCHEMISTRY Burkina Faso
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Hematological Alterations in an Eastern Sudanese Chronic Kidney Disease Patient Population
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作者 Mohammed Omer Abaker Gibreel Sundus Kamal Ibrahim +4 位作者 Wijdan Abdel Aziz Hassan Manar Yahia Mahjoub Leyla Mohammed Kheir Hamid Hibatellah Majzoub Abbas Nuha Fouzi Mohammed 《Open Journal of Urology》 2024年第6期359-367,共9页
Background: Chronic Kidney Disease (CKD), associated with a slow and progressive loss of kidney function over a period of several years, is an important clinical disaster with an increasing rate of morbidity and morta... Background: Chronic Kidney Disease (CKD), associated with a slow and progressive loss of kidney function over a period of several years, is an important clinical disaster with an increasing rate of morbidity and mortality especially in the least developed countries. Many hematological parameters are thought to alter dramatically during the course of the disease. These include white blood cells, red blood cells, and platelets. Methods: We tried, retrospectively, to evaluate the peripheral blood hematological alterations in a group of patients undergoing hemodialysis in an eastern Sudan dialysis center to add local medical information. Results: Anemia (Low hemoglobin and hematocrit) was detected in 94% of the patients’ group. Mean Erythrocyte count (3.32vs.4.76 (×109/L)), Hemoglobin concentration (9.4vs.13 (g/dl)), Hematocrit (28.7vs.38.7 (L/L)) and platelet count (296 vs. 238 (×109/L)) were significantly lower in the patients’ group than in the control group (P-values Conclusion: Five out of eight studied parameters (Red cell count, hemoglobin, hematocrit, mean cell hemoglobin concentration, and platelets count) have shown a significant alteration in CKD patients. As the complete blood count (CBC) test is the most utilized test in clinical laboratory practice, these alterations may be considered as early indicators for CKD. Furthermore, all patients with CKD must be routinely checked for these alterations. 展开更多
关键词 Chronic Kidney Disease Chronic Renal Failure Hematological alterations CBC Eastern Sudan HEMODIALYSIS
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ASTER data processing and fusion for alteration minerals and silicification detection:Implications for cupriferous mineralization exploration in the western Anti-Atlas,Morocco
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作者 Soufiane Hajaj Abderrazak El Harti +4 位作者 Amine Jellouli Amin Beiranvand Pour Saloua Mnissar Himyari Abderrazak Hamzaoui Mazlan Hashim 《Artificial Intelligence in Geosciences》 2024年第1期96-113,共18页
Alteration minerals and silicification are typically associated with a variety of ore mineralizations and could be detected using multispectral remote sensing sensors as indicators for mineral exploration.In this inve... Alteration minerals and silicification are typically associated with a variety of ore mineralizations and could be detected using multispectral remote sensing sensors as indicators for mineral exploration.In this investigation,the Visible Near-Infra-Red(VNIR),Short-Wave Infra-Red(SWIR),and Thermal Infra-Red(TIR)bands of the ASTER satellite sensor derived layers were fused to detect alteration minerals and silicification in east the Kerdous inlier for cupriferous mineralization exploration.Several image processing techniques were executed in the present investigation,namely,Band Ratio(BR),Selective Principal Component Analysis(SPCA)and Constrained Energy Minimization(CEM)techniques.Initially,the BR and SPCA processing results revealed several alteration zones,including argillic,phyllic,dolomitization and silicification as well as iron oxides and hydroxides.Then,these zones were mapped at sub-pixel level using the CEM technique.Pyrophyllite,kaolinite,dolomite,illite,muscovite,montmorillonite,topaz and hematite were revealed displaying a significant distribution in relation with the eastern Amlen region lithological units and previously detected mineral potential zones using HyMap imaging spectroscopy.Mainly,a close spatial association between iron oxides and hydroxide minerals,argillic,and phyllic alteration was detected,as well as a strong silicification was detected around doleritic dykes unit in Jbel Lkest area.A weighted overlay approach was used in the integration of hydrothermal alteration minerals and silicification,which allowed the elaboration of a new mineral alteration map of study area with five alteration intensities.ASTER and the various employed processing techniques allowed a practical and cost effective mapping of alteration features,which corroborates well with field survey and X-ray diffraction analysis.Therefore,ASTER data and the employed processing techniques offers a practical approach for mineral prospection in comparable settings. 展开更多
关键词 Remote sensing ASTER Hydrothermal alteration mapping SPCA CEM Kerdous inlier
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Extraction of Mineral Alteration Zone from ETM+ Data in Northwestern Yunnan,China
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作者 赵志芳 张玉君 +1 位作者 成秋明 陈建平 《Journal of China University of Geosciences》 SCIE CSCD 2008年第4期416-420,共5页
Alteration is regarded as significant information for mineral exploration. In this study, ETM+ remote sensing data are used for recognizing and extracting alteration zones in northwestern Yunnan (云南), China. The ... Alteration is regarded as significant information for mineral exploration. In this study, ETM+ remote sensing data are used for recognizing and extracting alteration zones in northwestern Yunnan (云南), China. The principal component analysis (PCA) of ETM+ bands 1, 4, 5, and 7 was employed for OH alteration extractions. The PCA of ETM+ bands 1, 3, 4, and 5 was used for extracting Fe^2+ (Fe^3+) alterations. Interfering factors, such as vegetation, snow, and shadows, were masked. Alteration components were defined in the principal components (PCs) by the contributions of their diagnostic spectral bands. The zones of alteration identified from remote sensing were analyzed in detail along with geological surveys and field verification. The results show that the OH^- alteration is a main indicator of K-feldspar, phyllic, and prophilized alterations. These alterations are closely related to porphyry copper deposits. The Fe^2+ (Fe^3+) alteration indicates pyritization, which is mainly related to hydrothermal or skarn type polymetallic deposits. 展开更多
关键词 mineral alteration extraction from ETM+ data PCA OH^- alteration Fe^2+ (Fe^3+) alteration northwestern Yunnan China
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Relationship between Landslides, Geologic Structures, and Hydrothermal Alteration Zones in the Ohekisawa-Shikerebembetsugawa Landslide Area, Hokkaido, Japan
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作者 Hiroyuki Maeda Takashi Sasaki +3 位作者 Kazuyuki Furuta Katsuhiro Takashima Akihiro Umemura MasanoriKohno 《Journal of Earth Science and Engineering》 2012年第6期317-327,共11页
This paper elucidates the relationship between landslides, geologic structures, and hydrothermal alteration zones based primarily on X-ray powder diffraction and uniaxial compressive strength tests on weakly weathered... This paper elucidates the relationship between landslides, geologic structures, and hydrothermal alteration zones based primarily on X-ray powder diffraction and uniaxial compressive strength tests on weakly weathered and hydrothermally altered rocks from the Ohekisawa-Shikerebembetsugawa landslide area in Teshikaga Town, Hokkaido, Japan. The OHS (Ohekisawa slide) occurred on a dip slope of sedimentary rocks from the Upper Miocene Shikerepe Formation within a homocline, and also on weathered and hydrothermally altered rocks within the boundary area between the hydrothermal smectite zone and smectite-bearing mordenite zone. The SHS (Shikerebembetsugawa slide) occurred on a dip slope of sedimentary rocks from the Upper Miocene Hanakushibe Formation within wavy folds and was also controlled by a cap rock of Teshikaga Volcano Somma Lava. The SHS occurred also on weathered and hydrothermally altered rocks within the boundary area between the hydrothermal smectite zone and smectite-bearing laumontite zone. The mechanical properties of smectite, smectite-bearing mordenite, and smectite-bearing laumontite zone weakly weathered rocks indicate that they are very weak, soft rocks. These landslides are regarded as HAZLs (hydrothermal alteration zone landslides). The hydrothermal alteration yielding smectite is thus closely related to these two ancient landslides, suggesting that the potential for HAZLs within a hydrothermal area can be assessed based on the swelling clay mineral-beating hydrothermal alteration types, dip slope, and cap rock. 展开更多
关键词 HAZL (hydrothermal alteration zone landslide) swelling clay mineral-bearing hydrothermal alteration zone weatheredand hydrothermally altered soft rock dip slope cap rock.
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