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MinerGeochem V1.0:一个全新的矿物地球化学数据信息系统
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作者 黄小文 《矿物岩石地球化学通报》 CAS CSCD 北大核心 2024年第4期767-774,共8页
矿物是人类认识地球及地外天体的一把钥匙。随着现代原位分析技术的快速发展,矿物地球化学数据呈现指数增长,积累了大量数据,但这些数据结构复杂,且无统一的标准和格式,阻碍了矿物大数据的再利用和相关的对比研究。鉴于矿物地球化学数... 矿物是人类认识地球及地外天体的一把钥匙。随着现代原位分析技术的快速发展,矿物地球化学数据呈现指数增长,积累了大量数据,但这些数据结构复杂,且无统一的标准和格式,阻碍了矿物大数据的再利用和相关的对比研究。鉴于矿物地球化学数据对解决各类地球科学问题的优势,以及它们复杂的数据结构和体量呈指数增长的趋势,本研究基于计算机信息技术、Web应用、关系数据库、GIS等开发了一个矿物地球化学数据信息系统(MinerGeochem)。该系统由信息硬件基础设施、操作系统/数据库系统、服务组件和应用模块组成。功能模块有用户管理模块、网站内容版块、数据管理版块、记录管理版块、系统配置版块、GIS数据可视化和数据导入导出等模块组成。数据维度有矿床数据、矿物数据、实验数据和文献数据四类数据结构,每类数据包含多个属性,数据通过其属性相关联,实现了任一数据属性的搜索和获取。数据标准化及数据上传采用Excel模版批量处理,简单快捷。MinerGeochem界面简单,使用方便,有望成为地学数据库的重要组成部分,为地学工作者提供数据支持。 展开更多
关键词 矿物 地球化学 数据库 信息系统 WEB技术
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High-pressure minerals and new lunar mineral changesite-(Y) in Chang’e-5 regolith 被引量:1
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作者 Jing Yang Wei Du 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第2期90-97,共8页
Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide oppor... Forty-five years after the Apollo and Luna missions, China’s Chang’e-5 (CE-5) mission collected ∼1.73 kg of new lunar materials from one ofthe youngest basalt units on the Moon. The CE-5 lunar samples provide opportunities to address some key scientific questions related to theMoon, including the discovery of high-pressure silica polymorphs (seifertite and stishovite) and a new lunar mineral, changesite-(Y). Seifertitewas found to be coexist with stishovite in a silica fragment from CE-5 lunar regolith. This is the first confirmed seifertite in returned lunarsamples. Seifertite has two space group symmetries (Pnc2 and Pbcn) and formed from an α-cristobalite-like phase during “cold” compressionduring a shock event. The aftershock heating process changes some seifertite to stishovite. Thus, this silica fragment records different stagesof an impact process, and the peak shock pressure is estimated to be ∼11 to 40 GPa, which is much lower than the pressure condition forcoexistence of seifertite and stishovite on the phase diagram. Changesite-(Y), with ideal formula (Ca_(8)Y)◻Fe^(2+)(PO_(4))_(7) (where ◻ denotes avacancy) is the first new lunar mineral to be discovered in CE-5 regolith samples. This newly identified phosphate mineral is in the form ofcolumnar crystals and was found in CE-5 basalt fragments. It contains high concentrations of Y and rare earth elements (REE), reaching upto ∼14 wt. % (Y,REE)2O3. The occurrence of changesite-(Y) marks the late-stage fractional crystallization processes of CE-5 basalts combinedwith silicate liquid immiscibility. These new findings demonstrate the significance of studies on high-pressure minerals in lunar materials andthe special nature of lunar magmatic evolution. 展开更多
关键词 evolution minerALS BASALT
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The optimal atropine concentration for myopia control in Chinese children: a systematic review and network Metaanalysis 被引量:1
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作者 Xiao-Yan Wang Hong-Wei Deng +7 位作者 Jian Yang Xue-Mei Zhu Feng-Ling Xiang Jing Tu Ming-Xue Huang Yun Wang Jin-Hua Gan Wei-Hua Yang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1128-1137,共10页
AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia... AIM:To figure out whether various atropine dosages may slow the progression of myopia in Chinese kids and teenagers and to determine the optimal atropine concentration for effectively slowing the progression of myopia.METHODS:A systematic search was conducted across the Cochrane Library,PubMed,Web of Science,EMBASE,CNKI,CBM,VIP,and Wanfang database,encompassing literature on slowing progression of myopia with varying atropine concentrations from database inception to January 17,2024.Data extraction and quality assessment were performed,and a network Meta-analysis was executed using Stata version 14.0 Software.Results were visually represented through graphs.RESULTS:Fourteen papers comprising 2475 cases were included;five different concentrations of atropine solution were used.The network Meta-analysis,along with the surface under the cumulative ranking curve(SUCRA),showed that 1%atropine(100%)>0.05%atropine(74.9%)>0.025%atropine(51.6%)>0.02%atropine(47.9%)>0.01%atropine(25.6%)>control in refraction change and 1%atropine(98.7%)>0.05%atropine(70.4%)>0.02%atropine(61.4%)>0.025%atropine(42%)>0.01%atropine(27.4%)>control in axial length(AL)change.CONCLUSION:In Chinese children and teenagers,the five various concentrations of atropine can reduce the progression of myopia.Although the network Meta-analysis showed that 1%atropine is the best one for controlling refraction and AL change,there is a high incidence of adverse effects with the use of 1%atropine.Therefore,we suggest that 0.05%atropine is optimal for Chinese children to slow myopia progression. 展开更多
关键词 ATROPINE China children and adolescents MYOPIA network Meta-analysis
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Nutrition impacts of non-solid cooking fuel adoption on under-five children in developing countries 被引量:1
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作者 Yalin Tang Yuhe Guo +1 位作者 Gang Xie Chengfang Liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期397-413,共17页
This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demogra... This paper examines the nutrition impacts of using non-solid cooking fuel on under-five children in developing countries.We draw on data from more than 1.12 million children in 62 developing countries from the Demographic and Health Surveys(DHS).Results from both fixed effects(FE)and instrumental variable(IV)estimates show that using non-solid cooking fuel significantly improves the nutrition outcomes of under-five children.Compared with their peers from households mainly using solid fuel,children from households mainly using non-solid fuel exhibit a lower probability of experiencing stunting(by 5.9 percentage points)and being underweight(by 1.2 percentage points).Our further investigation provides evidence for several underlying mechanisms,such as improved indoor air quality,induced reduction in children’s respiratory symptoms,benefits on maternal health,and reduction in maternal time spent on fuel collection or cooking.Heterogenous analyses suggest that the nutrition benefits of using non-solid cooking fuel are more prominent among boys,children above three years old,and those from households of lower socioeconomic status,rural areas,and Southeast Asia. 展开更多
关键词 non-solid cooking fuel nutrition benefits under-five children developing countries
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Association of preschool children behavior and emotional problems with the parenting behavior of both parents 被引量:1
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作者 Su-Mei Wang Shuang-Qin Yan +4 位作者 Fang-Fang Xie Zhi-Ling Cai Guo-Peng Gao Ting-Ting Weng Fang-Biao Tao 《World Journal of Clinical Cases》 SCIE 2024年第6期1084-1093,共10页
BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.... BACKGROUND Parental behaviors are key in shaping children’s psychological and behavioral development,crucial for early identification and prevention of mental health issues,reducing psychological trauma in childhood.AIM To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children.METHODS From October 2017 to May 2018,7 kindergartens in Ma’anshan City were selected to conduct a parent self-filled questionnaire-Health Development Survey of Preschool Children.Children’s Strength and Difficulties Questionnaire(Parent Version)was applied to measures the children’s behavioral and emotional performance.Parenting behavior was evaluated using the Parental Behavior Inventory.Binomial logistic regression model was used to analyze the association between the detection rate of preschool children’s behavior and emotional problems and their parenting behaviors.RESULTS High level of parental support/participation was negatively correlated with conduct problems,abnormal hyperactivity,abnormal total difficulty scores and abnormal prosocial behavior problems.High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children.High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms,abnormal conduct problems,abnormal hyperactivity,abnormal peer interaction,and abnormal total difficulty scores in children(all P<0.05).Moreover,paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors(all P>0.05),after calculating ratio of odds ratio values.CONCLUSION Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children.Overall,the more supportive or involved the parents are,the fewer behavioral and emotional problems the children experience;conversely,the more hostile or controlling the parents are,the more behavioral and emotional problems the children face.Moreover,the impact of fathers’parenting behaviors on preschool children’s behavior and emotions is no less significant than that of mothers’parenting behaviors. 展开更多
关键词 children Preschool age PARENTING BEHAVIORAL Parenting problems
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Research progress of CO_(2) capture and mineralization based on natural minerals
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作者 Chenguang Qian Chunquan Li +5 位作者 Peng Huang Jialin Liang Xin Zhang Jifa Wang Jianbing Wang Zhiming Sun 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第6期1208-1227,共20页
Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant ... Natural minerals,such as kaolinite,halloysite,montmorillonite,attapulgite,bentonite,sepiolite,forsterite,and wollastonite,have considerable potential for use in CO_(2) capture and mineralization due to their abundant reserves,low cost,excellent mechanical prop-erties,and chemical stability.Over the past decades,various methods,such as those involving heat,acid,alkali,organic amine,amino sil-ane,and ionic liquid,have been employed to enhance the CO_(2) capture performance of natural minerals to attain high specific surface area,a large number of pore structures,and rich active sites.Future research on CO_(2) capture by natural minerals will focus on the full utiliza-tion of the properties of natural minerals,adoption of suitable modification methods,and preparation of composite materials with high specific surface area and rich active sites.In addition,we provide a summary of the principle and technical route of direct and indirect mineralization of CO_(2) by natural minerals.This process uses minerals with high calcium and magnesium contents,such as forsterite(Mg_(2)SiO_(4)),serpentine[Mg_(3)Si_(2)O(OH)_(4)],and wollastonite(CaSiO_(3)).The research status of indirect mineralization of CO_(2) using hydro-chloric acid,acetic acid,molten salt,and ammonium salt as media is also introduced in detail.The recovery of additives and high-value-added products during the mineralization process to increase economic benefits is another focus of future research on CO_(2) mineralization by natural minerals. 展开更多
关键词 natural mineral carbon dioxide capture MODIFICATION composite material carbon dioxide mineralization
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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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Determination and Quantification of Proximate and Mineral Composition for 20 Improved Sorghum Varieties Grown in Machache, Lesotho
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作者 Malefane Ts’ephe Puleng Letuma +4 位作者 Karabelo Khomongata Fisseha Itanna Mamoipone Sebitia Monica Lephole Pitso Masupha 《Food and Nutrition Sciences》 CAS 2024年第8期744-758,共15页
Twenty varieties of improved sorghum were grown in Machache at the Department of Agricultural Research station, located (29˚22'60"S and 27˚52'0"E) in the central foothills of Lesotho in Maseru distri... Twenty varieties of improved sorghum were grown in Machache at the Department of Agricultural Research station, located (29˚22'60"S and 27˚52'0"E) in the central foothills of Lesotho in Maseru district. The varieties were planted in a randomized complete block design. At maturity, they were harvested, dried, threshed, milled and analyzed in the crop science laboratory at the National University of Lesotho. The proximate and mineral contents were analyzed from samples in a completely randomized design with three replicates. The proximate composition parameters measured were crude proteins, crude fiber, crude fat, moisture content, and carbohydrates. The minerals analyzed were, phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and magnesium. The results showed the nutritional contents ranging from (4.7% - 16.16%), (0.35% - 2.10%), (1.25% - 4.00%), (71.60% - 84.06%), (5.53% - 10.18%), for protein, fat, fiber and carbohydrate, and moisture content, respectively. Mineral content ranged from (1342.96 - 3500.34 mg/kg), (25.97 - 185.25 mg/kg), (50.71 - 511.71 mg/kg), (29.35 - 4542.13 mg/kg), (577.19 - 3041.52 mg/kg), (0.25 - 4.07 mg/kg), (1.96 - 18.61 mg/kg), (67.14 - 122.96 mg/kg), (4.73 - 11.39 mg/kg) for phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and manganese respectively. The following varieties were found to have the highest and appreciable amounts of nutrients and minerals that are crucial in the country diet;protein content was KARI Mtama 1, zinc, IESX 16 2533-SB-SSI-19, and iron IESX 16 2535-SB-SSI-34. 展开更多
关键词 VARIETIES SORGHUM PROXIMATE minerAL
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Assessment of Some Secondary Metabolites, Minerals and Alcohol Content of Noni Juice Obtained by Fermentation of Morinda citrifolia L. Fruit from Senegal
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作者 Ndèye Adiara Ndiaye Mame Ndew Mbaye +3 位作者 Lahat Niang Modou Dieng Nicolas Cyrille Ayessou Ndeye Coumba Kane Touré 《American Journal of Plant Sciences》 CAS 2024年第7期577-588,共12页
The fruit of Morinda citrifolia L., commonly known as noni, has an extensive history of use as a food and traditional medicine around the world. Adding value to Morinda citrifolia L. products, particularly the fruit, ... The fruit of Morinda citrifolia L., commonly known as noni, has an extensive history of use as a food and traditional medicine around the world. Adding value to Morinda citrifolia L. products, particularly the fruit, could be one way of building resilience in vulnerable farming households. The aim of this study was to determine the secondary metabolite and mineral composition of noni juice obtained by fermenting the fruit of Morinda citrifolia L. Fruits were collected in August 2022 from the local field in Thiès region, West of Senegal. Extraction yields were determined and the secondary metabolites were determined using conventional analytical methods. Calcium, magnesium, iron, sodium and potassium were determined by atomic absorption spectrophotometer coupled with a CCD detector. The results show that an average fruit mass (503.2 ± 110.96 g) consists of 171.44 ± 50.01 g pulp and 34.06 ± 10.35 g seeds. The traditional extraction yield of noni juice is 16.46% after three weeks of fermentation. The contents of total polyphenols, flavonoids and tannins obtained in noni are 608.97 ± 4.53 mg EAG/100mL, 7.78 ± 0.01 mg EQ/100mL and 0.191 ± 0.01 mg EC/100mL respectively. The ethanol content of noni varies from 3.57 to 5.23 mL/100mL during extraction. Noni has a high calcium content with a concentration of 383.79 ± 33.23 mg/L. This is followed by a good concentration of magnesium, potassium and sodium, at 278.47 ± 26.30, 187.43 ± 10.7 and 155.95 ± 28.66 mg/L respectively. Noni also has an iron content of 202.15 ± 0.05 mg/L. 展开更多
关键词 Morinda citrifolia L. JUICE ALCOHOL Total Phenols FLAVONOIDS TANNINS minerALS
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Expert consensus on pediatric orthodontic therapies of malocclusions in children
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作者 Chenchen Zhou Peipei Duan +22 位作者 Hong He Jinlin Song Min Hu Yuehua Liu Yan Liu Jie Guo Fang Jin Yang Cao Lingyong Jiang Qingsong Ye Min Zhu Beizhan Jiang Wenhua Ruan Xiao Yuan Huang Li Rui Zou Yulou Tian Li Gao Rui Shu Jianwei Chen Renkai Liu Shujuan Zou Xiaobing Li 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第2期186-196,共11页
Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of~260 million children... Malocclusion,identified by the World Health Organization(WHO)as one of three major oral diseases,profoundly impacts the dental-maxillofacial functions,facial esthetics,and long-term development of~260 million children in China.Beyond its physical manifestations,malocclusion also significantly influences the psycho-social well-being of these children.Timely intervention in malocclusion can foster an environment conducive to dental-maxillofacial development and substantially decrease the incidence of malocclusion or reduce the severity and complexity of malocclusion in the permanent dentition,by mitigating the negative impact of abnormal environmental influences on the growth.Early orthodontic treatment encompasses accurate identification and treatment of dental and maxillofacial morphological and functional abnormalities during various stages of dental-maxillofacial development,ranging from fetal stages to the early permanent dentition phase.From an economic and societal standpoint,the urgency for effective early orthodontic treatments for malocclusions in childhood cannot be overstated,underlining its profound practical and social importance.This consensus paper discusses the characteristics and the detrimental effects of malocclusion in children,emphasizing critical need for early treatment.It elaborates on corresponding core principles and fundamental approaches in early orthodontics,proposing comprehensive guidance for preventive and interceptive orthodontic treatment,serving as a reference for clinicians engaged in early orthodontic treatment. 展开更多
关键词 PERMANENT stated children
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Evaluation of the Care of Children Aged 0 to 10 Years Hospitalized for Severe Malaria at the Tambacounda Health Center, Senegal
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作者 Tidiane Gadiaga Aminata Fall +10 位作者 Alioune Badara Gueye Siré Sagna Bayal Cissé Mouhamadou Faly Ba Médoune Ndiop Babacar Gueye Samba Cor Sarr Sylla Thiam Elhadji Ba Konko Ciré Jean Louis Abdou Ndiaye Issa Wone 《Advances in Infectious Diseases》 CAS 2024年第3期581-594,共14页
Introduction: Malaria remains a public health priority in Senegal, particularly in Tambacounda, where it is one of the main causes of child mortality. The objective of this work was to evaluate the care of children un... Introduction: Malaria remains a public health priority in Senegal, particularly in Tambacounda, where it is one of the main causes of child mortality. The objective of this work was to evaluate the care of children under 10 years of age hospitalized at the Tambacounda Health Center and the factors associated with recovery. Methods: An analytical, retrospective, and descriptive cross-sectional study with exhaustive recruitment of children 0 to 120 months hospitalized at the Tambacounda reference health center for severe malaria (according to WHO criteria) between 1 January 2018 and 31 December 2021 was performed. Data collection was done through a questionnaire. Records, hospitalization records, and treatment records were the sources of collection. Data entry and analysis were performed on Epi Info 7.2 and R. Results: A total of 481 children hospitalized with severe malaria were recruited. The highest number of cases was recorded in 2018 (33.05%). In the four years of the study, peaks were always observed between October and November and the highest peak in November 2020 with 95 cases. The mean age was 65.64 months with a standard deviation of 29.28 months and a predominance of male (53.43%). The majority of people were admitted from the outpatient clinic (57.79%) and the rest (42.21%) on the recommendation of a peripheral health post. All hospitalized patients had a positive RDT and/or a positive thick drop. However, the sharp decline at admission or during hospitalization was positive in 93.80% of patients in our series, negative in 5.20% and not achieved in 1.00%. Seizures and severe anemia topped the list of signs of severity with 45.94% and 8.11%, respectively. In terms of evolution, for all hospitalized patients, there were 81.29% recovery, 10.19% referral to the Tambacounda regional hospital center for hospitalization, 4.99% death, 0.83% discharge and 2.70% unknown evolution. There was a statistically significant association between recovery without referral from a health post (OR = 1.85), absence of 2 or more signs of severity (OR = 1.82), absence of seizures (OR = 1.51), prostration (OR = 2.78), cardiovascular shock (OR = 6.67), coma (OR = 7.69), lack of evidence of biological severity (OR = 3.70), and hypoglycemia with blood glucose less than 0.4 g/L (OR = 5.88). Conclusion: In addition to the routine malaria prevention and management strategies implemented in Tambacounda, and the early referral of cases of severe malaria from health posts to the health center, all children hospitalized for severe malaria with certain symptomatology such as coma, prostration, cardiovascular shock, etc. Seizures and/or hypoglycemia should be systematically referred to the regional hospital to increase their chance of recovery. 展开更多
关键词 Severe Malaria children Tambacounda Senegal
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Basalt Petrology, Water Chemistry, and Their Impact on the CO_(2) Mineralization Simulation at Leizhou Peninsula Sites, Southern China
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作者 Jinglian Jiang Pengchun Li +4 位作者 Changyou Xia Jianxin Cai Muxin Liu Yongbin Jin Xi Liang 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期583-598,共16页
Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest ... Mineral carbonation, which precipitates dissolved carbon dioxide(CO_(2)) as carbonate minerals in basaltic groundwater environments, is a potential technique for negative emissions. The Leizhou Peninsula in southwest Guangdong province has extensive basalt, indicating a promising potential for CO_(2) storage through rapid mineralization. However, understanding of the basic geological setting, potential, and mechanisms of CO_(2) mineralization in the basalts of the Leizhou Peninsula is still limited. The mineralization processes associated with CO_(2)storage at two candidate sites in the area are investigated in this paper: Yongshi Farm and Tianyang Basin(of the dried maar lake). Petrography,rock geochemistry, basalt petrophysical properties, and groundwater hydrochemistry analyses are included in the study. Numerical simulation is used to examine the reaction process and its effects. The results show that basalts in the study areas mainly comprise plagioclase, pyroxene, and Fe–Ti oxides, revealing a total volume fraction exceeding 85%. Additionally, small amounts of quartz and fayalite are available, with volume fractions of 5.1% and 1.0%, respectively. The basalts are rich in divalent metal cations, which can form carbonate minerals, with an average of approximately 6.2 moles of metal cations per 1 kg of rock. The groundwater samples have a pH of 7.5–8.2 and are dominated by the Mg–Ca–HCO3 type. The basalts demonstrate a porosity range of 10.9% to 28.8%, with over 70% of interconnected pores. A 20-year geochemical simulation revealed that CO_(2) injection dissolves primary minerals, including anorthite, albite, and diopside, while CO_(2)mineralization dissolves precipitation secondary minerals, such as calcite, siderite, and dolomite. Furthermore, a substantial rise in pH from 7.6to 10.6 is observed in the vicinity of the injected well, accompanied by a slight reduction in porosity from 20% to 19.8%. Additionally, 36.8% of the injected CO_(2) underwent complete mineralization within five years, revealing an increasing percentage of 66.1% if the experimental period is extended to 20 years. The presence of abundant divalent metal cations in basalts and water-bearing permeable rocks in the Leizhou Peninsula supports the potential for mineral carbonation in basalts, as indicated by the geochemical simulation results. Additional research is necessary to identify the factors that influence the CO_(2) mineralization, storage, and sensitivity analysis of basalt in the Leizhou Peninsula. 展开更多
关键词 CO_(2)mineralization mineral carbonation Basalt carbonation Geochemistry simulation Leizhou Peninsula
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Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)
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作者 Rania Ben Aissa Wiem Ben Aissa +2 位作者 Said Tlig Lassaad Ben Aissa Abdessalem Ben Haj Amara 《Acta Geochimica》 EI CAS CSCD 2024年第2期366-384,共19页
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ... The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary. 展开更多
关键词 Ore-formingfluids mineral geochemistry mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia
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Epidemiological, Diagnostic, Therapeutic, and Prognostic Profile of Non-Tuberculous Community-Acquired Purulent Pleurisy in Children at the Bouaké University Hospital Center, 2017-2021
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作者 Yapo Thomas Aba Christian Yao +6 位作者 Pacôme Monemo Richard Azagoh-Kouadio Iburaima Akandji Noelle Gonné Jean-Marie Karidioula Vincent Achi Vincent Kouadio Asse 《Advances in Infectious Diseases》 CAS 2024年第1期220-232,共13页
Introduction: In Côte d’Ivoire, there is a scarcity of data on children’s purulent pleurisies. Objective: This study aims to elucidate the epidemiological, diagnostic, therapeutic, and evolutionary facets of no... Introduction: In Côte d’Ivoire, there is a scarcity of data on children’s purulent pleurisies. Objective: This study aims to elucidate the epidemiological, diagnostic, therapeutic, and evolutionary facets of non-tuberculous purulent pleurisies in pediatric patients. Methods: A retrospective analysis was conducted using the medical records of children aged one month to fifteen years with purulent pleurisies at Bouaké University Hospital Center from January 2017 to December 2021. Results: The study identified 124 cases of purulent pleurisies, constituting 18% of lower respiratory tract infections and 0.8% of all hospitalizations. The majority of these cases (69%) were in children between 1 and 24 months of age. Prominent symptoms included dyspnea (85.5%), O2 saturation below 95% in room air (76.6%), respiratory distress (68.5%), cutaneous-mucosal pallor (63.7%), and fever (43.5%). Radiological findings predominantly showed right-sided pleurisy (62.1%). The pleurisy was often extensive (78.2%), accompanied by pneumothorax (37.1%), alveolo-interstitial opacities (8.1% of cases), and abscess formations (1.6%). Pleural fluid cultures were positive in 46.9% of cases, with Staphylococcus aureus (75%, methi-S) identified among 32 bacteria. Initial antibiotic treatment was empirical, favoring oxacillin (53.2%) or amoxicillin-clavulanic acid (53.2%) in dual (42%) or triple therapy (33%) with gentamicin (64.1%) and/or metronidazole (21.8%). Treatments also included pleural drainage (68.5%) or repeated evacuation punctures (33.1%), and blood transfusion (39%). The mortality rate was 18.8%. Conclusion: Non-tuberculous purulent pleurisy remains a significant concern in pediatric hospitalizations at the CHU of Bouaké, marked by high mortality rates. 展开更多
关键词 Community-Acquired Purulent Pleurisies children Mortality Bouaké
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Mineral Geochemistry of Apatite in the Jiama PorphyrySkarn Deposit,Tibet and its Geological Significance
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作者 YANG Yang TANG Juxing +8 位作者 ZHANG Zebin TANG Pan XIE Fuwei RAN Fengqin YANG Zongyao YANG Huaichao BAI Yun SUN Miao QI Jing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期399-415,共17页
The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemi... The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic system.However,the mineral chemistry of its accessory minerals remains under-examined,posing challenges for resource assessment and ore prospecting.Utilizing electron microprobe analysis and LA-ICP-MS analysis,this study investigated the geochemical characteristics of apatite in ore-bearing granite and monzogranite porphyries,as well as granodiorite,quartz diorite,and dark diorite porphyries in the deposit.It also delved into the diagenetic and metallogenic information from these geochemical signatures.Key findings include:(1)The SiO_(2) content,rare earth element(REE)contents,and REE partition coefficients of apatite indicate that the dark diorite porphyry possibly does not share a cogenetic magma source with the other four types of porphyries;(2)the volatile F and Cl contents in apatite,along with their ratio,indicate the Jiama deposit,formed in a collisional setting,demonstrates lower Cl/F ratios in apatite than the same type of deposits formed in a subduction environment;(3)compared to non-ore-bearing rock bodies in other deposits formed in a collisional setting,apatite in the Jiama deposit exhibits lower Ce and Ga contents.This might indicate that rock bodies in the Jiama deposit have higher oxygen fugacity.Nevertheless,the marginal variation in oxygen fugacity between ore-bearing and non-ore-bearing rock bodies within the deposit suggests oxygen fugacity may not serve as the decisive factor in the ore-hosting potential of rock bodies in the Jiama deposit. 展开更多
关键词 APATITE METALLOGENESIS mineral geochemistry PORPHYRY JIAMA TIBET
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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review
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作者 Shi-min Zhen Da-zhao Wang +2 位作者 Zhong-jian Zha Hai-jun Bai Jiang Wang 《China Geology》 CAS CSCD 2024年第3期533-550,共18页
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi... The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit. 展开更多
关键词 mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton mineral exploration engineering
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Respiratory complications of propofol,sevoflurane,and dexmedetomidine anesthesia for fiberoptic bronchoscopy in children aged 1 month to 3 years:a randomized trial
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作者 Amir Shafa Mohammad Montasery +4 位作者 Sedighe Shahhosseini Majid Keivanfar Asieh Maghami Mehr Mahtab Ebrahim Babaei Mohammad Jafari 《南方医科大学学报》 CAS CSCD 北大核心 2024年第9期1631-1636,共6页
Objective To evaluate the effect of propofol,sevoflurane,and dexmedetomidine on respiratory complications inchildren undergoing fiberoptic bronchoscopy(FOB).Methods This double-blind randomized clinical trial was cond... Objective To evaluate the effect of propofol,sevoflurane,and dexmedetomidine on respiratory complications inchildren undergoing fiberoptic bronchoscopy(FOB).Methods This double-blind randomized clinical trial was conductedamong 120 children aged 1 month to 3 years undergoing FOB.The patients were randomized into 3 groups(n=40)foranesthesia induction with sevoflurane inhalation,1 mg/kg propofol,or 1μg/kg dexmedetomidine before bronchoscopy,andthe changes in hemodynamic parameters,sedation level,and respiratory complications during and after the procedure wereassessed.Results The patients'heart rate during bronchoscopy was significantly lower and the mean arterial blood pressuresignificantly higher in dexmedetomidine group than in sevoflurane and propofol groups(P<0.05).Cough duringbronchoscopy did not occur in any of the cases in propofol group,while the highest frequency of cough was recorded indexmedetomidine group.The incidence of laryngospasm in the propofol group(12.5%)was significantly lower than those insevoflurane and dexmedetomidine groups(30%and 32.5%,respectively)(P<0.05).Conclusion Sevoflurane and propofol aresafe and suitable for anesthesia induction in children below 3 years of age undergoing diagnostic FOB and can achieve bettersedative effect and lower the incidences of cough and respiratory complications as compared with dexmedetomidine. 展开更多
关键词 fiberoptic bronchoscopy PROPOFOL SEVOFLURANE DEXMEDETOMIDINE children
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Metallogenesis of the Baidi Au-Sb deposit, southwest Guizhou Province, China: mineralogical and geochemical evidence from sulfur-bearing minerals
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作者 Jun Yan Yong Xia +2 位作者 Qinping Tan Zhuojun Xie Guosong Ji 《Acta Geochimica》 EI CAS CSCD 2024年第2期199-213,共15页
The Baidi Au-Sb deposit, which contains 8 t of Au and 10,979 Mt of Sb, is a typical and rare paragenetic deposit located in southwestern Guizhou Province, China.Previous studies have focused on individual ores, but ha... The Baidi Au-Sb deposit, which contains 8 t of Au and 10,979 Mt of Sb, is a typical and rare paragenetic deposit located in southwestern Guizhou Province, China.Previous studies have focused on individual ores, but have not combined them to identify their paragenetic mechanism or metallogenic regularity. Therefore, we used field investigations, microscopic observations, and in situ analyses to identify the spatial distribution, mineral paragenesis, compositional evolution, and metallogenic material sources of the ore bodies. We also determined the Au and Sb paragenetic characteristics and the metallogenesis of the deposit. The main Au-bearing minerals in the deposit were early(Apy1–2) and late(Apy3) stage arsenopyrites, as well as pre-mineralization(Py1), mineralization(Py2–5), and late mineralization(Py6–7) stage pyrites. The main Sb-bearing minerals were stibnite(Snt), skinnerite, bournonite,and valentinite. The minerals formed in the order of Py1,Py2–3 + Apy1, Py4–5 + Apy2, Snt, and Py6–7 + Apy3.The δ34S values of the arsenopyrites and pyrites ranged from-5 to 5‰, while those of stibnite were mostly less than-5‰ in the later mineralization stages. Sulfur was provided by deep magmatic hydrothermal fluids, but sedimentary sulfur was added in the later stages. Moreover,the trace elemental contents fluctuated and eventually became similar to those of the sedimentary strata. By comprehensively considering the ores along with the geological characteristics of the deposit, we determined that deep magma provided the Au during ore formation. Later tectonic changes provided Sb from the sedimentary strata,which precipitated along fault expansion areas and produced Au and Sb paragenesis. 展开更多
关键词 Au-Sb mineralization ARSENOPYRITE Pyrite STIBNITE Metallogenetic process
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Evaluation of Interferon-Gamma Release Assay Testing and Tuberculin Skin Test for Early Diagnosis of Tuberculosis in Children and Adolescents
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作者 Yelda Sorguç Miray Çelebi Yılmaz +4 位作者 Yüce Ayhan Yakup Yaman Şener Tulumoğlu Aybüke Akaslan Kara İlker Devrim 《Open Journal of Pediatrics》 2024年第3期558-567,共10页
Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country ... Background: This study aimed to evaluate the diagnostic value of interferon-γ release assay (IGRA), a sensitive microbiological diagnostic method, in children and adolescents with suspected tuberculosis in a country with a high burden of tuberculosis. Method: This study included 581 children and adolescents aged 4 - 19 years who were suspected of having tuberculosis, were latently infected with Mycobacterium tuberculosis, and had received at least one dose of BCG vaccine between April 17, 2019, and February 24, 2021. The study evaluated the TST results of 106 patients who had a positive Quantiferon test and were suspected of having tuberculosis. Results: The study included 581 patients aged between 4 and 19 years. Of these, 106 patients tested positive for the Quantiferon test, while 19 were indeterminate and 456 were negative. The Quantiferon test positivity rate was 18.24%. Among the 106 QFT-Plus-positive cases, 23 patients also tested positive for TST. The difference in distribution was found to be statistically significant. Conclusion: The QFT-Plus test is considered an alternative to TST and other microbiological diagnostic methods for early tuberculosis diagnosis, particularly in children and adolescents. 展开更多
关键词 Interferon Gamma Release Assay children Tuberculin Test children Latent Tuberculosis
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Petrogenesis, oxidation state and volatile content of Dongga tonalite in the Gangdese belt, Xizang: Implication for porphyry Cu mineralization
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作者 Liqiang Zhang Xilian Chen +3 位作者 Shaohao Zou Deru Xu Xuena Wang Hua Wang 《Acta Geochimica》 EI CAS CSCD 2024年第2期280-295,共16页
The Gangdese belt in Xizang has experienced both Jurassic subduction and Cenozoic continental collision processes, making it a globally renowned region for magmatic rocks and porphyry copper deposits. Numerous Jurassi... The Gangdese belt in Xizang has experienced both Jurassic subduction and Cenozoic continental collision processes, making it a globally renowned region for magmatic rocks and porphyry copper deposits. Numerous Jurassic intrusions have been identified in the belt. Apart from the quartz diorite porphyry in the large Xietongmen deposit, the Cu mineralization potential of other Jurassic intrusions in this belt remains unclear. This study presents zircon U–Pb dating and trace elements, apatite major and trace elements as well as published whole-rock geochemical and isotopic data of the Dongga tonalite in the central part of the Gangdese belt, aiming to reveal the petrogenesis, oxidation state, volatile content, and Cu mineralization potential of this intrusion. The Dongga tonalite has a zircon U–Pb age of 179.4 ± 0.9 Ma. It exhibits high whole-rock V/Sc values(8.76–14.6), relatively low apatite CeN/CeN*ratios(1.04–1.28), elevated zircon(Eu/Eu*)Nvalues(an average of 0.44), high Ce4+/Ce3+values(205–1896), and high ?FMQ values(1.3–3.7), collectively suggesting a high magmatic oxygen fugacity. The Dongga tonalite features amphibole phenocrysts, relatively high whole-rock Sr/Y ratios(20.3–58.9), and lower zircon Ti temperatures (502–740 ℃), reflecting a high magmatic water content. Estimation of magmatic sulfur content(0.002–0.024 wt%) based on apatite SO3contents indicates an enriched magma sulfur content. Combined with previous studies and the collected Sr–Nd–Hf isotopes, the Dongga tonalite is derived from juvenile lower crust related with subduction of the Neo-Tethys oceanic slab. When compared with Xietongmen orebearing porphyries, the Dongga tonalite exhibits remarkable similarities with the Xietongmen ore-bearing porphyries in terms of magma source, tectonic background, magmatic redox state, and volatile components, which indicates that the Dongga tonalite has a high porphyry Cu mineralization potential, and therefore, provides important guidance for the future mineralization exploration. 展开更多
关键词 TONALITE Zircon APATITE mineralization potential Dongga area Gangdese belt
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